Apply fresh lube every week or so.
Once a month or after any time out in the rain, degrease, clean, and relube the entire drivetrain.
Retension chain as necessary, just enough to keep from having play in the cranks.
Pump tires every couple weeks.
Wipe down frame any time I don't like how dirty it is.
Other adjustments (headset, brakes, etc.) as necessary.