Darn, had a nice list and got logged out, first choose where you are going to live and work carefully. Its expensive and jobs are at a minimum. Know this as my daughter was going to go to college there but is second thinking since we were there last week checking it out. Next, find a well maintained beater with no quick release anything. Everything should be bolted down and tight. Get a good U lock and look carefully when you lock up your bike, you'll see others locked up go there. Keep it light so its easy to throw on buses and carry up stairs. I have an Xtracycle which I wish I had taken instead of my single speed only because it would have been easier to ride my daughter around on, she locked her bike in front of a church afte the 1st hill, a beach crusier with 24 inch wheels, so we took the bus, but if I had the X it would not have fit the rack on the bus. So think of how you plan on getting around also, I am used to hills at a high altitude so San Fran wasnt too bad. You can also map out rides that will take you around hills.
Good luck, I am envious as I have always wanted to live in the city. I wanted to be a bike messenger back in middle school, hell I still do.