Polar bear is something I haven't used in years. I know someone who has a full skin, and he parted with a little for me to tie him some pike flies. It is one of the nicest hairs I have worked with. At least the piece he gave me was. A couple of things that I found useful tips were.

Tie 2 sizes of fly together. A large one and a smaller one next. I usually prep for a dozen at a time so I would count out six of each size of hook. Tie the large one. Use the longest hair for the wing as normal. Then tie the smaller one using the hair that you stripped out of the first bunch for the wing. The under fur you are left with goes into a tub to make dubbing. (I use this with Arctic fox on salmon flies as well).

To really lock the wing in place use a locking turn. This does away with the need for glue in the wing roots. All you do is take a turn around just the wing after you have tied it in with a couple of turns. Then tie that turn down. It puts a small kink in the hair and makes it very secure. If you want the wing to stand up a little from the shank, like a Scandinavian salmon fly, make your locking turn wing side of the turns you initially tied it in with. If you want a low wing make the locking turn around the butts of the hair and tie down before trimming off.

Now I just need to work out how to "liberate" the rest of that skin!

Cheers,
A.