I explicitly define some of my activities as intensive, others as extensive. If I just sit down with a magazine or book or homepage and read for pleasure or for the sake of some interesting content then I accept that I don't learn many new words. Only if I feel that the whole comprehension of a passage hinges on a specific word I pick a dictionary or look it up (and I still prefer paper dictionaries). Sometimes I do notate it on a sheet of paper, but unless that sheet of paper is reserved for words in a specific language it is fairly unlikely that I'll ever do more about it.
If I study intensively I do take pains to find out what the new words mean. For instance I often sit down and copy a text to a folded piece of paper with a margin to the right for new words, and the words I notate here
will be used in one of my special three-column wordlists. When I make the wordlist I'll often look it in a dictionary to check its morphology and possible other meanings - even if it comes from a bilingual text where I in principle already have a translation. The point is that even human translations may be wrong, and a word may also be translated in a slightly skewed way because of a specific context, and I don't want to memorize translation errors. I have written about Google Translate in
this thread, and I have written a lot about my personal wordlist layout in my
guidebook so I won't repeat the whole lot here - but if I didn't use wordlists my passive vocabulary would in my languages would be much smaller than it is, and I would take longer to learn to read for instance WIkipedia articles or newspaper articles in new and weak languages. With some more conversation training such a background could also ease my transition to active speaker, but alas, I don't do much about that side of language learning when I'm at home. But without my use of wordlists I couldn't activate my weak languages fast during travels so they are essential even for making languages active.
So you don't get the whole sermon about the concrete layout here, but I would like to emphasize that this layout only is part of the tale. When I mamorize a word with its translation it is important to produce memory hooks. Mostly they will be associations based on sound. It is not necessary to invent 'funny histories' that cover the whole word - mostly it is enough to remember that a word sounds somewhat like something in another language, and it is better with two partial and not very precise associations than one perfect associtation which it takes several minutes to come up with. It is also important to
use the memory hooks while you still remember them, so repetition is essential, but in my experience the repetition has to come shortly aftert the original memorization - otherwise you'll just have forgotten one thing more. The whole point in memorization is to form some kind of semantic halo around every new word, And context? Well, some of my wordlists are based on texts, and there I have the context in the text itself - but other wordlists are based directly on dictionaries, and there the only context is the alphabetical order. The better I know a language the less I need a full sentence to remember new words.