How do you felt?

Choose a yarn that felts, ie an animal fiber that has not been mercerized (turned into "superwash") and is not blended with much of a fiber other than animal hair. For example, too much acrylic will prevent a wool blend from felting. Knit or crochet the project using needles about three sizes larger than you would ordinarily use with yarn of that thickness. If there isn't enough space between the stitches it will not felt well. Try felting a test swatch before committing to a large project.

When the project (or swatch) is ready to felt, put it in a zippered pillowcase and into the clothes washer along with two or three pairs of jeans and a dash of detergent. Set the controls to maximum heat and maximum aggitation (the setting for extra dirt will have the most aggitation). Check in about five minutes to see if the project is starting to shrink yet. Keep setting the cycle back to the beginning when you check so that it never reaches the spin cycle. Different yarns in different colors, projects, and washing machines will felt at different rates. So check every five minutes until it starts to shrink. Once it starts it will progress quickly, so check more often. When the project is the desired size and/or texture, stop. If in doubt, stop. You can always felt more, but you cannot unfelt if you go too far.

Squeeze out the excess water and shape to dry. If it's a purse, stuff it with towels or a small box wrapped in plastic wrap so it will dry in a pleasing shape. For a hat, cover your head in plastic wrap and wear the hat until dry for a perfect fit.