Here's a few of my comments about what i've been doing and what i've been learning through my experience.
1. I like whip and tongue more than other styles of grafting. I like locking them in and then wrapping them up nice and tight with 1" teflon plumbing tape before giving them a nice warm wax bath. I really like this tape, it's flexible and easy to work with, and cheap.
2. Sharp knife makes your life easier.
3. When working with larger caliper rootstocks, don't try to make one big glory cut going all the way through. In fact I dont even go across the whole rootstock. I just widdle down an edge on one side a little bit at a time with broad strokes. I'll try and get a picture of what I mean next time i graft some more trees. Most of these rootstocks are much larger than any of the scions i have. So the key for me is one getting a nice long flat smooth cut. I also examine the rootstock and try to find a nice 2" straight section where i'll make my cut. I do the same on the scion. I look for a nice straight section of the wood, so many are crooked and jagged. I find the straight side so I can hopefully match up one side of the root to one side of the scion. Again i'll only get one side to match so I make sure both are nice and straight and hopefully I get a good 1-1.5" line up of the cambiums. My tongue cuts are usually about 3/8" long. Some of my scions are very small so the key to adding a tongue to a small scion is going very slow and gently working your knife through the wood.
4. Take your time, do not rush. Take your time, do not rush. Take your time, do not rush. There will be less blood and your success rate will be much higher if you just take your time. Especially on the back cut, I just like to go real nice and slow gently rocking my knife back and fourth letting it do the work, just dont force it, thats how you'll draw blood.
Won't know how much success i have until august in my opinion, but I like the way things are going so far. Things seem to be lining up pretty well on my end.
Cheers
-Ed