Place your forearm securely on a bench or desk. Apply a small amount of massage cream onto a trigger point ball, then firmly press into the muscles along your forearm. Apply pressure starting at your hand and then slowly but firmly, press the ball into your wrist extensors and then roll the ball towards your elbow. Repeat this movement and motion for a minute or so.

The massage cream eliminates friction between the ball and your skin. You can do this without cream however it may be much more irritating to your skin and harder work for yourself.
The more pressure that you apply, the more firm the myofascial release will be. As your tissues become less sensitive you may want to increase the amount of pressure that you use.