You will need: Dish Soap, Legacy 100% wool stuffing, Felt, A sink, kiddie pool, bathtub or even big bowls filled with very warm water and a drop or two of handwashing dish soap just enough that your water feels slippery between your fingers.
Create a core for your rock using a handful of wool stuffing, pull off thin a piece of your roving and lay core on top. Place another thin layer of roving and roll up in the opposite direction. Roll as you would a ball of yarn, changing direction and tucking in corners. Sometimes it helps to have slightly moist hands. Don’t worry if it’s not right you can always unroll and re-roll if needed. Place rattle in center of your core if you are using one, they are water tight so just throw them on in, you will want to keep your rock on the smaller side, 4 inches or less, so rattle sound will still be clear. Your finished rock will be about two thirds the size of this looser form. If you want to make your rock larger you can add more colored roving to outside, or start with a larger core.
If you want to add streaks of another color to the outside, pull of wisps of streak colors and wrap around outside.
Saturate your “rock” with water by gently submerge in water, you may want to cradle it in the palm of your hand since the wool will want to drift apart, especially if you didn’t roll tightly enough. Hold rock underwater until no more bubbles surface.
Step 3 Pass rock from one hand to another, carefully as if it is an egg, this will help toughen the wool rock and keep it from coming apart. This is the hardest part of wet felting and it’s really not that hard. After about 20 or so passes you will notice your rock will appear less stringy and more solid. This will take a few minutes and you’ll know your done when your wool feels more firm and looks more secure.
Keep rolling, squeezing between you hands, you do not have to treat it as delicately as before. Try to keep your rock very wet and a little soapy. As it felts, the wool will shrink and become firmer, and you can become more aggressive with it.
This firming will happen naturally if you try to speed the process your felt will buckle and create a kind of wrinkled look but your making rocks so that might be what you want, I did this with the round flat rock and I think it makes the rock look more realistic (on the bottom right hand side of the picture below.)
Step 4 While felting try to keep your water warm, the warmer the water the faster your rocks will felt. Some people swear that dipping your ball from warm water into cold and back again speeds up the felting process, this just annoys me leave me with more dishes to clean so I just use the one bowl. Keep working it until you can’t separate the fibers from the surface of your “rock” anymore. Rinse soap from wool, a final rinse in vinegar water will return a woolly texture and feel to the outside.
While still wet you can manipulate your rock to flatter or more jagged looking forms, work it with your hands, bang it on the corner of a counter or on the concrete outside to make it flatter, use your imagination. You can also place your “rocks” in the dryer on high to felt them further although this does tend to round them out a bit!