as a native Russian speaker i can only support
Leopejo's idea to try finding access to Polish through Russian,
if you speak it well.
1) beware of false friends, there are not just a few of them!
2) beware of the differences in grammar and pronounciation, especially
stressing words correctly. Although not that tricky, they have to be kept
in mind all the time. Otherwise your Polish will just remain similar to
Russian or may resemble Ukrainian to a Pole.
4) our teacher said that some foreign students had come to
learning Polish and persisted in it through the Polish music,
so probably it could help you, too?
5) personally i enjoy reading the Polish literature, both translated
and in the original. It's difficult in the beginning, though; hence, you
could probably start by reading short news (like wiadomosci.pl)
I wish you luck whatever method you prefer!
Zycze cie sukcesu! Udachi!