If you cut off the prefix and the suffix, then you're left with the base word. OK, so associate that word with meanings: not only the dictionary meaning, but what you think of when you say it, what it sounds like, when you once used it, what other words it rhymes with (in English and Thai!), etc. Connect the word with feelings, colours and impressions. Look up the etymology and see if there's a meaning behind the word. Eg. "companion" refers to "eating bread together". Using the word will help you remember it. Good luck!