Ok where do I start...
Charles - thank you very much. The tree had a nice growth form when I bought it so it was easy to keep it going.
Alan, Brent, and ohjustaguy,
I usually use the whip n tongue method to graft a dormant scion on the tree. Sometimes i use a saddle graft just to change things up and do something different. You can do certain grafts in the growing season, but I haven't had much success once the temps are breaking 90. You can look up side veneer grafts on youtube, that's what I'll use if the scion isn't dormant. I learned how to graft just researching on the internet and watching youtube videos about it. I use an art knife from hobby lobby (looks kind of like a scapple) and I just experimented with blades to see what I liked. The real grafting knives where just too expensive, and this way, when the blade gets dull, I just throw it and grab a new one. I ordered my grafting tape and wax from ebay, and I always wrap the scions with parafin wax (it's a paper wax you can cut into strips to wrap with) it holds the moisture in, and when the buds are ready to go, they just pop right through it. I've had the most success whip n tongue and cleft probably. The cleft I usually use when the scion is smaller than the branch you want to graft to. Anyway, the most important thing when grafting in my opinion is sanitation, I always rinse my blade with alcohol before each cut, or each new graft.
Here is a helpful link to get you started
http://www.ces.ncsu.edu/depts/hort/hil/grafting.html