every 4-8 weeks, depending on how well you heal. take a read of this if you haven't already, it's pretty sound advice. http://dermaroller.owndoc.com/dermaroller-instructions.pdf

use iodine after stamping.

use vitamin e lotion as a part of your routine daily as well it really plumps up the skin makes scars less noticible

I used the dermastamp for the first time a couple of weeks ago. The one I'm using is 1.5 mm and it's for a deep scar on the bridge of my nose. When I used it I heard some popping and there was a tiny bit of blood, but it didn't hurt too much. I think I was a bit too cautious. How often should I use it?

Not more than once every six weeks based upon what I have read. It takes approximately six weeks for fibroblasts to produce collagen.