My routine varies. If it's already been 24 hours, I might bump up my stats for my forum, using the link that I have posted on my own site, and then as long as I'm here, I usually reply to topics that interest me. If it's not time for me to bump up stats yet, then I just browse around and search for topics that interest me to reply to.
For me, I would say that I actually work back up from the bottom of the forum towards the top. Admin Discussion and then graphics exchange really interests me, and so maybe that's why I start from the bottom.
I usually check PM's first then the staff forum, reports and then the CM forum and then i bounce between the other forums depending on what i feel like viewing.