Welcome, a rockman sling is a tough one to start out with so don't get discouraged if it's not as pretty as some of the more expierienced members slings.
 
I started out the same way with a denim pouch and pleather. I went through a pouch every slinging practice because it tore through untill I figured out that duct tape wouldn't tear like that. So I made slings that way for awhile and then found this site and then my sling making had a lot more creativity.  
 
There are lots of knowledgeble slingers on here, if you are intent on learning a lot, you will.
 
 

Welcome aboard.  
 
What part of Canada?

Hi, woody2;
    The Rockman is the very first "good" sling that I ever made.  I used the same tutorial that you are using.  If you pay attetion you should be OK.  It's an excellent tutorial.  If you do get discouraged and want to go to a tape sling for a while try using medical tape (the good, cloth based type, not the cheap paper kind) instead of duct tape.  I find it's a lot more durable plus it's easy to work with.  Duct tape crinkles after a while.  Medical tape never does.
 Welcome to our site.