Friendly Plastic is an easy to use thermoplastic that I've been using for some time. I used to make my claws completely using friendly plastic but found that over time the tips would deform and discolor if they were not painted so I've switched over to resin. For my fox I'm using DVC small feline claws.

Please note that while the plastic doesn't get that hot, any water beads on the plastic you take out can be very hot if you're not careful. Heat a cup of water for about 2 minutes in the microwave depending on the container you're using. Pour in a handful of the beads until they turn clear and fish out a dime sized portion. Flatten it out to about an inch wide and wrap it around the lip of the claw. Place the claw up against your finger and squish the material tight around your finger. I try to keep the plastic thin but not too thin because I use hot glue to secure them to the paws and don't want the glue to melt the thermo plastic. I keep a a cup of ice water on hand to dip the claw in once it looks the way I want to harden it faster.

This technique will make each claw finger specific so once you take them off, label each with a sharpie. Once you have them all done, plug in your hot glue gun and put the claws on one hand. When I sew the paws, I leave the tips of each finger open. Pull the paw on over the claws so they stick out of the finger tips. Pull down the fur and put a dot of hot glue on the top of the plastic. Secure the fur down and do the same on the underside. I only use a small bit of glue to make sure the heat doesn't melt through and burn my finger. Make sure to bend your finger before the hot glue cools to make sure the finger won't be too tight.

Once the claw is secured in place, repeat for the other claws. You can then take the paw off and finish securing the fur to the claws. Trim the fur around the claws as necessary.