I would start by not getting dragged into discussions about Russia and Ukraine.
Start a communist club if there isn't one already, host weekly meetings and advertise at the club promotions. You'll be building a brand and reputation, so put lots of effort in at the start, and likeminded individuals will join along.
How's that Ukrainian counter offensive going? I don't support either side but Russia is clearly the lesser evil. People in Crimea and Donbass have the right to self determination.