The classic( method for memorizing words is to use flashcards: small cards, on one side of which you write a few words in Russian and on the other side their translation. You can put some of them in your pocket or wallet and every time you have five seconds you can guess and check a word.

( Barry Farber's book, How to learn a language or something, made this popular.

Today spaced repetition software is very useful. These are kind of electronic flashcards, on which you input new words and translations (or explanations in your target language). The program shows you one side of the card (either the Russian word or the English translation) and you have to guess the correct answer. After showing you the correct answer, the program asks you how well you remembered it, typically from 0 (absolutely forgot) to 5 (very easy to remember). According to your answer, the program decides when to show the card again. For a very easy word that you always remember well, the times between repetitions of the same card soon rise to months, instead a difficult word is repeated every few hours at the beginning, every few days later.

The most known commercial program is Supermemo. An old version of Supermemo is free to download. Free alternatives are Mnemosyne and Anki, which is what I use.

These programs exist both for PC and portable devices.

EDIT: you may find some existing word lists for some of these programs on the internet, but you'll learn a word better if you take the time to write it into the program. Kind of frustrating though, having to change from English to Russian keyboard for every word.

Oh, and nothing impedes you to use phrases instead of words.