Get them all
This technique is very well suited to learning by immersion. You acquire new words by carrying a dictionary everywhere (anything electric has them on these days) and then making a note of new words wherever you come across them. These form your daily vocabulary list. Learn the words, revisit the source, move on to a related text or video for repetition. Keep going until you remember all (or 80%, 70%...it's your choice!) of the words from your list, then find a new source. Your memory will build the connection between source and vocab, allowing you to remember the word by where you learnt it from.