If you like the shape you can leave it alone, you're in no need for heavy pruning when ornamental.

konrad,
Wickson is one of the best 'edible' crab varieties - high-quality fruit with high brix and excellent flavor, though fairly small, as crabs are wont to be - though, like most apples, I'm sure it's 'ornamental' when in bloom.

Yes, I plan to eat them and make cider. The reason I ask is The fedco website says crabs require little to no pruning and recommends allowing the trees to assume their own unique form. although Wickson is not listed with the other edible crabs.

Ah..oh,..sorry, somehow I missed Wickson.
Then I would do some pruning,..don't get the branches mangled up,..get some light in. I also cut back ends that it can hold a load of apples. But let it grow a year or two.