Misterpaul;
Just a few ideas.
1. When wrapping the hackle, make sure your thread is hanging at the rear of where the head will be formed rather than at the hook eye. This way, the first thread wrap when you bind down the hackle will help push back the barbs on the lst wrap of hackle.
2. Another small thing that will help your thread go where you want it is to spin the bobbin to take the twists out of the thread when you leave it hang to wrap the hackle. This will help your first thread wrap stay back where you want it.
3. Try selecting a hackle from a different cape, and see if it helps the problem. Some capes just won't cooperate.

If things still aren't going well in a few weeks, stop by and see me just down the road at the Sowbug Roundup in Mountain Home, AR. I've had so many tiers in my classes, both beginners and advanced, that have trouble with the traditional dry flies that I've decided to tie them at one or more of my scheduled sessions. I'll be tying all day Thursday, and Saturday afternoon.
Good Tying,
Arnie