I used sidewalks but that's sometimes considered an asshole move. I just had a beach cruiser bike which was not really suited for roads, and did not bike on very populated sidewalks (for instance I'd never bike in Carytown). If a normally unpopulated sidewalk was populated, I'd get off and walk the bike. (and still avoided most hassling)

Some roads have bike lanes, how well they are maintained and how well people pay attention really varies.

It really just depends on you being polite and aware of yourself and the space you're taking up.