Bonkers here is made in a really dense thick fur, lovely to hug but more of a challenge to work with !
if you have chosen one of the denser furs, you will find it realy helps to trim the fur along the seam allowance. You will have far less fur trapped in the seam and stitching will be so much easier too (by hand or machine : )
It is always advisable to release the trapped fur from the seams. Both inside, and out too. A teasel brush with wire bristles is ideal, but you can also use a blunt needle (wool needle) or wooden cocktail stick to tease the fur out too.
When cutting out , try to cut into the backing, leaving as much of the fur in tact as you can. It helps to take tiny snips with the tips of your scissors as you cut.
I've found that drawing a small craft blade along the backing is perfect and leaves the fur alone. Do be very careful though and be aware that this will not work on trickier shapes : )
Some furs have a loosely woven backing which allows the fur to stretch and can allow your bear to become mishapen : (
If you are making a floppy character, that may be fine, but if you want your bear to keep in shape, you need to add an interfacing to firm up the fur. You dont want to put all your creative energy into a beautiful bear's face to find that it distorts as soon he receives his first hug !
You have a choice of iron or sew-on interfacings. Choose whichever suits your style. Iron-on can be attached to the complete piece of fur before using it. If using a sewn-in type use your sewing machine to attach around the outher edge (see right)
Most furs have a strong backing with no stretch and can be used "as is"