I have played and cum in panties for many years. One of my favorite techniques involves three panties at the same time.
First I will put on one pair of panties and stick my balls and cock out the left (could be right if you prefer) leghole.
Then I will put on another pair of panties and stick my balls and cock through the right leghole of those panties.
Finally I will put on a third panty that covers everything up.
The purpose of the first two panties is to hold my balls in center position and pooched out a little in front of my body so they wiil be rubbed by the third panty as I rub and stroke myself on the outside of this panty occasionally pulling on the panty itself to add to the fun and excitement. Using the three panties enhances the lovely sensation of nylon or silk or satin rubbing all my parts. It also allows me to cover three panties at once with a nice load of cum.
Finally when I do shoot my load the ouside or final panty contains all the cum and the first two pairs also help soak up the cum and I have had the pleasure of cumming in three panties at once.
Finally there is not much to cleanup since all the cum is usually on the panties which I usually let dry as they hang on the clothes line.