It is not the fastest, but easy way to get some faction points is by doing a lower level flashpoint that you can solo. You can run by all mobs and just kill the bosses and get bonus xp for beating them. At the end you just pick light side or dark side and you can keep repeating dungeon over and over. At 35 I have just been doing MR over and it takes about 10-15 minutes and I get ~5k xp ~15k credits and the faction, not bad if you are bored and LFG.
Just run through until you get to a starting point zone out yell your LFG... go back in finish it up.