Hi Steve,

It's better to learn complete sentences than isolated words. On the flashcards you make, I recommend jotting down the nominative form (or infinitive, if it's a verb) and then mention what case the word is in in your example sentence. Also be sure to note accent shifts. So, if I were learning the word for "water", it would look something like this:

I want water, please.

Я хочу воду, пожалуйста. (accus.)
nom = вода

I'd also just learn the forms of a word on a need-to-know basis. Again, re: "water", you're much more likely to use it in it's nom or accus case than, say, the dative.