The worst turbulence I ever experienced was not in cloud but in clear air over the Alps in a private jet!
We had departed Nice on a northerly SID and had severe turbulence between FL200 and FL300! 45 degree wing drops, cupboards flying open , climb rate 1500 to 2000 fpm above normal.
The worst you will get in cloud is running into a CB in which case reduce speed and ride it!
But turbulence in cloud should not be any greater an issue than turbulence out of it !
Pace