Which memory drills and abilities may improve language learning capacity?

I want to train a set of abilities that may help me on learning a language. Which drills may help on that endeavor?
I have thought on:

  • Memorizing random characters.
  • Memorizing random phrases.
  • Memorizing random words.

Danke.

EDIT: Could you guys also recommend me websites and/or applications in which I could do those drills for free? PS: It cannot be memory league.