Prepping stuff the night before.
For me, having a specific place for my commuting stuff helps too, so I know it's all there, and don't have to rush around in the morning, looking for everything. During the summer, I leave everything on the bike. During the winter, I have a place to hang up my cold weather gear.
Not getting a flat is important if you're on a tight schedule. My bike has puncture resistant tires, plus I carry all of the things needed to repair a flat.