I am planning on making 1 or 2 swimmers for a 6" top tier swimming pool cake.  I also want to have two legs sticking up like someone is doing a handstand.  I've never done sculptures before, so how much of the toothpick do I need to stick into the cake to keep things standing up.  The people may not even need toothpicks.  They may be able to just be placed on the cake.  I plan to use fondant with some gumpaste, so they should harden.  I'm most curious about the legs.  I don't want them to fall over.  Should I use something else, like skewers or dowels?  Not sure if I could find some short enough???  Thank you!

Ideally, you would use as long as you can, like touching the base board your cake is on, if you are doing a whole person that is maybe as tall as your cake is and they are standing. For just the legs sticking up, you could get away with a toothpick, since the height of the objects is less. The same for sitting figures. I use (raw!) spaghetti for figures because it comes long and it's easy to get the length you want. It's also edible...it wouldn't be nice to eat but better than chowing down on a toothpick. It will snap under some force though of course.
 

Please use spaghetti instead of toothpicks, Toothpicks can be lethal if accidently ingested. They cannot be picked up on an X-ray. Spaghetti is much safer and you can break it off at whatever length you need it to be. 

Great!  Thank you ladies!  I bought some bamboo skewers, but I can do spaghetti instead.  Good to know.