You Know More Than You Think
Studying a foreign language in high school and walking away for years does not mean you wasted your time. Let's explore why.

Unlocking the Knowledge You Already Have
Welcome, aspiring polyglot! Something many people miss when they embark on their second language acquisition process is that, often, you do not have to start at zero. With how easy it is to travel around the world and hear foreign languages nowadays it is all but certain that you know more words in your target language than you think.
More importantly, if you have studied the language before and are returning, even if it's been years, you are in a position that will facilitate your language learning experience. What matters most when thinking about language learning strategies is ensuring they are conducive to your success. That means ensuring you are capitalizing on the knowledge you already have, even if it is dormant.

Figuring out your language learning base
The first step in unlocking your base of knowledge is realizing just how many words from other languages are already part of your existing vocabulary. When you learn that "encore" means "again" in French, you can start to think about how you would use it when speaking French.
When you realize that "bailando", as in the hit song from Enrique Iglesias, means "dancing" you can start thinking about ways you would form a sentence using it. Which, hopefully, will spur your curiosity in understanding the suffix on the verb "bailar". Curiosity is a powerful tool in learning a new language.

Here are some other examples of shared words across languages you may or may not have heard before:
- Gesundheit - Abierto - Cerrado - Relleno
- Rendezvous - Cliché - Resumé - Memoire
- Fussball - Touché - A la carte - Aficianado
- Angst - Au naturel - Au revoir - Bon voyage
- Carte blanche - Doppelgänger - Kindergarten - En masse
- Entrepreneur - Fiasco - Lingua franca - Laissez faire

These are only a taste and as you pay attention to this phenomenon you will likely notice more and more that you can add to your lists. Once you have gathered all of the words that you know simply from common use, it is time to really start working your brain and attempt to remember what you can from the classes you have previously taken, if any. However, beware of the false friends.
When you sit down and take the time to read through a text in the language you have previously studied or watch a lyric video you will see that there are words you recognize. The excuse that "it's been a long time" or "I can read it but not very well" is really the only thing holding you back.
It will likely be slow at the beginning, but over time you will see more and more words you recognize and you will begin to build your confidence. When it comes to language acquisition, building your confidence is going to be paramount because you will take many, many blow to it over the course of this journey. For more on that you can check out this article:

As you go documentation is going to be important. A problem that many people run into is looking up the same word over and over again and it is because they are not writing the words down when they are looking them up. It may sound simple, but writing things down will improve your ability to recall the things you are learning.
By adding a physical dictionary to look things up in to your routine you will notice that not only are words sticking better, but you are learning new vocabulary words simply because you are consistently opening a dictionary. Again, curiosity is an essential piece of language learning.
When you track your progress, you will see that you do, in fact, know more than you thought and that you have quite a bit more to cover. An additional benefit is that you can go back and see how far you've come after a couple of weeks. Language acquisition is a slow process, but there is no reason for you to start back at zero if you spent years sitting in a classroom.

Once you have your base defined it is time to strengthen the foundation. Take time to ensure you truly understand the grammar rules your remember. List out vocabulary words that will help you to better express yourself building on what you already know. Practice your conjugations in context to ensure you are getting the correct usage time after time rather than in one off scenarios.
After spending some time reinforcing your foundation, you can start to build upon it. Develop your language skills by reading about things in which you are interested. Think about ways you can say things in a more eloquent and precise way. Find the best way to express yourself, not just a way to express yourself. The best way to do this is by adding new words to your repertoire.
Develop your language skills by expanding your vocabulary

Build around what you know. That is one of the most powerful language learning strategies of which you can take advantage. If you are a woodworker, you should listen to and watch videos about woodworking in your target language. By being targeted and intentional about the material you use to get your comprehensible input day in and day out you can take large steps rather than learning to crawl.
Because consistency is necessary for language learning, putting focus on areas where you already have a base of knowledge can help keep you interested. When you are interested, studying is easy; and when you study by reading about things you already know, you will find that many of the terms are similar. These confidence boosts will be important later as your momentum begins to die down.
Finally, by reading about things you are interested in, you will have ample opportunity to practice your language skills with context clues. At the end of the day, you do not need to know every word in a sentence to understand what the sentence is saying. This is true irrespective of whether it is your second language, your third language, or your native language. By using context clues to infer the meaning, you can narrow down what the word could possibly mean.
However, as mentioned above, there is no replacement for a physical bilingual dictionary. The best practice is to make your best guess and then verify by looking the word up in a dictionary and writing it down. Another advantage to this is, when you come back to these you will likely run into resources you had forgotten about and you can then take some time to check them out and see if you fair any better this go around.
Plug and chug grammar rules

As you are going through the language, especially in the beginning, you are likely going to be asking the question, "why" quite a bit. Especially when it comes to the grammar rules in many languages. Often there are more exceptions to the rules than there are rules and this can be confusing.
Not only that, but a grammar explanation that makes sense to one person may not make sense to another. This can result in people completely lost when trying to construct sentences which can be demoralizing. This is where many language teachers mess up in that they leave a lot of students lacking in grammatical comprehension.
What this normally comes down to is a focus on the wrong things. Whether it be endless conjugation charts, sentence mapping, or accent tests, the lessons are generally geared towards exam preparation. This makes sense, but it is not necessarily conducive to learning a new language. While it is imperative to learn and advance your understanding of grammar in your target language, drilling conjugation may turn you off of it entirely, again.

Rather than learning the grammar rules in the abstract, it may be beneficial to learn them in context. By reading and writing you will learn the grammar rules simply by being exposed to them so often. This, ideally, would spur your curiosity and have you investigating why things are the way they are. Once you understand the why you can begin to use it yourself. The average language learner will not do this, but if you do you may find your language acquisition goes more smoothly than it ever did before.
Bizarre as it may sound, by implementing systems in your language learning you will find that you are running into less walls and when you do plateau it is for less time. When you can see how other words can plug into different grammar structures you immediately unlock entire new ways to express yourself. It will be slow at first, but slowly you will notice that all the things you learned before were not completely forgotten.

Conclusion
For how many second language strategies exist, it is incredible that an idea similar to the language recovery discussed above is not more prominent when it comes to language learning strategies. Irrespective of your learning style, the time you spent learning something was not for nothing. When you see key words upon further investigation of this idea, you just might realize through your own self evaluation that you do, in fact, know more than you thought. Hopefully, this will convince you that it is worthwhile to continue on until fluency.
It takes time to truly develop your language skills, but it is a worthwhile endeavor. By building on the base you already have you will be able to jump leaps and bounds ahead of your competition. However, if you choose not to continue studying consistently, someone who is starting at zero will be able to pass you. Take advantage of the knowledge you already have, but if you want to start at zero with another language, that is completely understandable, too. Whatever you choose, choose learning a new language.

Learning a foreign language is no easy feat, it will be difficult irrespective of how you approach it. But you can do difficult things and be great, so continue to do difficult things and be great. I will be here by your side endeavoring to do the same.
Be sure to check out Second Language Strategies to catch up on anything you missed, find me on Twitter or Instagram for some short form content. If you are struggling to get speaking in your target language, join our Discord! I look forward to seeing everyone’s progress in the months and years to come.