1. Load Judy (or the character you are going to use).
2. Load a dress from the dynamic clothing library.
3. Go to frame 5, then load the sitting pose you want to use. (You
might want to check the pose before proceeding and correct it, if
necessary. For example, the pose "Sit on Chair 04" has Judy's
hands cut into her thigh. It's best to raise the hands a little above
4. Load the object that your figure is going to sit on. (In my test,
I just used the box primitive to simulate a sitting surface.)
5. Go to a side view and scale and position the object underneath the
sitting character. Note the scale amount, you'll need it in the next
6. Go to frame 1 (the scaled object will revert to its original
size). Scale the object to the same value as in step #5, then position
it behind the character. You don't have to put it very far behind, just
be sure that the dress is not touching it.
7. Go back to the main camera, if you wish, then enter the Cloth
8. Click on "New Simulation". A window will pop up where
you can enter some parameters. I left the end frame at 30 and checked
the "Cloth self-collision" option. Set the "Drape
frames" value at 4, then click OK.