Russian is a Category II language, with a quite complex grammar, and it takes even a good language learner about 1100 hours of intense learning and practice to master it. Among European languages, only Finnish, Estonian, Hungarian and Basque are harder.
If I were you, I would use a good systematic language course. A good example would be the "Colloquial Russian" series from Routledge :
http://www.omniglot.com/books/language/russian.htm