Choosing felting supplies depends first on what type of felting you plan to do, wet or dry. Both types involve binding the wool fibers closer together, producing a more solid material than the one with which you started. In either case, however, choosing the right type of wool is a key ingredient. Choosing the right supplies, such as zippered bags, felting needles and cushions, is important as well.
For wet felting, the most important felting supply is yarn that is 100% untreated wool, such as merino; wool blends often will not felt, and some wools are treated to prevent felting. Many yarn companies list on the label whether a yarn is suitable for felting, and inexpensive wool yarns can be found easily in large chain craft stores.
The other important supply in wet felting is a zippered bag, such as a pillow protector. The bag should be solid, not mesh like a lingerie bag. The felting process releases a lot of fiber and lint. Putting the object you’re felting into this bag will protect your washing machine from getting too clogged up.
Dry felting can be done with most any loose fiber from wool roving to dog hair. The best choice for needle felting is sheep’s wool because the rough coats of the fibers link together nicely. Wool types are named after the breed of sheep that produced them; Romney, Corriedale, and Leicester are some of the best choices for dry felting.
Other than the fiber, you need a few special felting supplies for the dry felting process. The most important item is a felting needle. These are thin, barbed needles about 4 or 5 inches (about 10 to 13 cm) long; the best option is probably a sampler pack which includes fine and coarse needles as well as three- and five-sided needles. There is not much difference in the quality of felting needles; most are inexpensive. You will need to buy multiple needles because the process of jabbing downward with the needles does cause them to break easily.
A cushion is an essential supply for dry felting as well. Cushion help to absorb the needles as they go through the wool and can help avoid sticking your fingers. A small square of high density foam at least 1 inch (2.5 cm) thick should do the job.
If you plan to do a lot of dry felting, you might consider investing in a set of hand carders. These are small brushes which allow you to blend different colors of roving. You typically can find carders in specialty stores; a more easily available option is to use a pair of slicker brushes, made for dogs, instead.
While most of these felting supplies can be found at craft stores, specialty yarn shops are another good place to find your supplies. The people working in the store often have experience with the various yarns and can give you a personal perspective on how easy the wool is to work with and how it looks after felting. There are also some good online shops for wool, which feature forums and blogs where you can post questions about particular yarns and get feedback from other crafters.
Ultimately, choosing supplies for felting comes down to personal preference. Knitting some test swatches or needle felting small projects is the best way to decide if you like the material. Many felters tend to stay with the same brand once they’ve found a wool they like, although you should be prepared to search again if your favorite material is discontinued.