Very simple marketing advice: Create an attractive thumbnail/cover that reflects a high quality version of the art in your comic (basically style should match, but you can bring out the extra polish and shine). Put thought into your story description, and proof read for errors. There's a good chance these are the first two things anyone will see in regards to your comic, so best foot forward. =)
Schedule Advice: Build a buffer! Unless you absolutely thrive on crunch time updating, try to finish several pages ahead of your update schedule, and release on a schedule that allows you to continue creating pages as fast or faster than they go live online. I also recommend building breaks into your schedule- for me thats a week long break mid chapter, and a month (or two) long break between chapters. I use this time to build my buffer back up, but it also accounts for things like sickness, injury, or study time that interrupts regular workflow.
Random: I just always recommend this for new users, but if you search "Nitty Gritty Tips" on the forums, there's a VERY useful series that covers advice on some of the difficult areas of comic making. I prefer the art ones, but I'm pretty sure there's some on marketing stuff and whatnot. You might find useful advice there, as a large number of the community pools resources and finds or creates examples of concepts. =)
(Sorry Dialusions! I don't know how I replied to you instead of the OP! XD )