To use Self Collision

1. If you have not already done so, apply a Muscle deformer on your object.
2. Select Muscle > Self/Multi Collision > Self Collision Grouping from the main menu bar.
3. In the window, specify a name for the grouping you want to create.
4. Select points for the first half of the area you want to collide. For example, select an upper arm region of points, and click the load selection button to load these point indexes into the window in the Pts A section.
5. Select the other half of the area you want to collide and load those points by clicking the button in the Pts B area.
6. Click Create New Grouping.

   This data is now stored on the Muscle deformer so that it knows which areas of your mesh to collide.

7. Select the Muscle deformer on the object.
8. In the Channel Box or Attribute Editor, set the selfCollision attribute to on.

   Collisions are computed.

9. Adjust the Self Collision, Self Rigidity and Self Volumize weights as desired. You can also adjust the attributes related to Self Collision in the Self Collision Grouping window.