The important thing with learning vocab is to make sure that it's a regular activity, because otherwise you just tend to forget whatever you learned on the way. But the method has to come from you: you can use flashcards, a whiteboard.... there are also very good apps that are available to learn vocabulary. A last thing is to have the words sorted out thematically in your head, this means that when you learn you want to separate them in a way that makes sense.