Aren't you that guy that ask this question like three days ago...
Any way you should at least make your skitty learn his/her last move before evolving it and also it wouldn't hurt if you ev train it before you evolve it.
Well I would let it lvl up to lvl 40 then evolve it.Mine is lvl 45 now and I still never evolved it.It's name is Skitit (I got it from a in game trade on Sapphire) and I use it in contst.I would not evolve it at all if I where you but you should at lvl 40