What do you want to change?
You can't change skincolor when the sim ist already made and in world...also skin-/head- and bodyfeatures (except tattoos) and I think eyecolor, won't be changable then.
You can change the body a little, but it's very limited and of course hair, make-up, clothes as you said.
There's a cheat for it though, I play on console, but I think it is: shift click on the sim, then the option to change sim should come up und you should be able to change everything (I havent tried it though).
Only other work arround I can think of is to save the household to your librairy, then delete them from world, click on the lot they where in and select "create new household", you go into CAS and load the household there and can edit them to your hearts desire till you put them back in the world.