There are alot of way to rotate the engine and I'm sure you'll get severla suggestions. I prefer to do it by hand to eliminate any possibility of it starting up.

When the PS belt slips (as mine does), I reach down with my left hand and rotate the crank balancer pully (the other end of the PS belt) while rotating the PS pump with a wrench in my right hand.

It requires some effort but is simple to do and you won't break anything.