I am learning Vietnamese. I've also said I was too old, didn't have brain for it, etc. But, I started looking in to HOW to learn a new language and found some help. Several videos by polyglots revealed that they used memory joggers to help learn new words. For instance,
to have in Vietnamese is "có," which is pronounced "caw." When that word fist popped up, I pictured a crow who "had" my keys and was flying away with them saying "caw."
After a couple of days, I didn't need those training wheels to remember that word. Yeah, this seems like a bit of mental gymnastics, but multiple people who have learned many languages explained they use similar tactics to remember new words. Just repeating via flashcards isn't very effective. There needs to be some context... and motivation helps.
