Paws and feet can be the easiest or hardest part of a costume... Creating servicable "character" hands and feet is often not too difficult; however, creating "realistic" hands and feet can be quite a challenge! This page provides some suggestions about different techniques you may want to use.
Sewn Paws and Mittens
Paws are often made along the lines of a glove pattern. This creates individual fingers and doesn't hamper the wearer's dexterity much. Additionally, these paws look great on character fursuits and they're easy to make!
Developing a good paw pattern can require a bit of time and skill, but it is well worthwhile. A simple two-part pattern can be made by tracing your hand on a piece of cardboard; then, enlarge the edges to allow for a seam allowance. This glove will not be as comfortable as a properly patterned glove, however, because the thumb is not sewn at a natural angle. But it will certainly serve you well. Once the pattern is finalized, it is sewn in fur. A lining may be added for extra padding and comfort.
A simpler option is to sew a fur mitten. There are no individual fingers, simply a flat area and a thumb; padding may be added inside to help smooth the mitten surface and prevent people from feeling fingers when shaking hands.
Alternatively, one can use a thinner fabric for the inside face of the paw. This allows you to manipulate objects with your fingers more easily. The extra bit of manual dexterity may be quite worthwhile, depening on the work duties of the costume. I used this technique to create paws for Jasmine Jester so that I'd be able to juggle.
The above designs assume that the paw is furred. But if a skin appearance is desired, cast latex is the way to go. When properly made, these paws can appear quite realistic, even including skin texture and veins.
The process for creating these paws is similar to how you would create other cast latex sculptures. An original sculpture is created on top of a lifecast. A negative mold is created from the clay sculpture. Latex is then slushed around inside the mold in successive coats to build up the final item.
One simple solution to creating furry feet is to make spats that fit over ordinary shoes. This is seen on a lot of rental and theater costumes since it allows the wearer to use their own shoes; in this way, the feet can fit a lot of different people.
A spat is simply a fur covering that fits around the shoe. The weight of the fur is not enough to keep it hanging down and covering the shoe, though. I like to run a couple of bands of elastic across the underside to keep it secured. The elastic bands run under the rubber soles of the shoe but don't seem to suffer much wear and tear.
Since feet can be tricky to create (they have lots of odd curves to them), spats can be a great option for beginners. Unlike some of the other techniques, spats are also easily washable.
Feet can be built from sheets of foam. For the feet of my panda costume, I tend to use half-inch thick foam. When making feet from scratch, I use one sheet for the sole of the foot and a second sheet that's cut and darted to form the curving body of the foot. Fur is then glued directly onto the foam; edges that tend to pull apart can be reinforced with a few hand-sewn stitches.
A better option is to construct foam feet on top of existing shoes. I like to use bedroom slippers; they're generally inexpensive ($10) and can be found in bargain bins. Regular shoes also work, though you need to design the shape of the foot such that you'll be able to reach the laces when putting them on.
Glue layers of sheet foam to the shoes to create the foot's shape. In the example shown, I'm creating large paws on top of a slipper. Foam is glued in place and then shaped with scissors. I also chose to add some claws, which are mounted into the foam toes. Fur is then glued over the top.
Latex feet may be made in the same way as latex paws. Here you can run into durability problems. Latex stand up pretty well in masks and hands, but walking on it can wear it down quickly. If you plan on making cast latex feet, plan on replacing them if the costume sees much outdoor use.
The advantage of latex feet is, obviously, realism. Feet, unless disguised with shoes, are often the weakest spot in a costume's appearance. Appearance is often passed over for durability.
The latex paws on this page are from werewolf costumes by the fine folks over at Running Wolf Productions.