I'm no expert at this but from my feeble attempts at this I can offer the following hints:
Hold the skin taut when cutting.
Cut from the back side of the pelt, .
On the cross cut strips be very careful to only cut through the skin, and not into the fur. I've lost 1/2 of the fur by cutting too deep on some strips.
Don't try to cut a strip the length of the pelt. Shorter lengths are easier to control.