Here's a few dubbing comments/tips, not really specific to your form or ability:
- Most people use way too much, like NightAngler says.
- Most people try to apply it too heavily in one pass. It is far better to grab a little at a time, just a few strands, and build up the bulk that way.
- When you pull the fibers from the package, they tend to be oriented at a right angle to the thread, and that's good for applying them. If you try to dub them in-line or parallel to the thread they may come off.
- Twist only in one direction as you said.
- It is very difficult to dub right up to the hook shank, so keep that in mind. Sometimes it is possible to slide the material along the thread a little.
- I haven't waxed my thread in years, whether it's uni-thread of UTC multi-strand. I think waxing tends to cover up bad technique when you get started tying.
- Synthetic dubbings like Superfine are difficult to get off or slide down the thread. It's always better to put on too little dubbing (in length along the thread) and add more later.
- Did I mention that most people use way too much!
Hope this is helpful to your tying.