Look into the crystal ball of your past to see where you went wrong (or right). What clues do you find there? If you've made mistakes where language-learning is concerned, you don't want to repeat them.
If you ever tried to learn another language and quit, why was that? What did you hate doing? What put you off? What did you lack? Was your approach (or that of the teacher) wrong? In what way? Was the timing wrong, or the setting, or your expectations?
Figure it out as best as you can. Make changes. Don't repeat the same mistakes.
If everything was wrong, then do everything the opposite! What can it hurt? Try things out and give them up until you latch onto the correct formula.
Think of Edison and all of those light bulbs that he went through!