i take the cutting from a sturdy branch. dip it in rooting hormone, and stick it in the rockwool.
you dont have to take it out of the rockwool, just plant it.
whats important is the temp and the humidity, make sure the rockwool doesnt dry out or stay soaking.
if you have the money to buy a cloner, go for it, but simple works.
the best method ive used is using rockwool. my attempt at building a cloner failed because i didnt have enough money to buy a new pump to push my mister heads, so i used an ultrasonic fogger and it overheated my reservoir.
the 3 plants i have in flower in the link in my signiture were all cloned into rockwool, no humidity dome, under 1x 105watt cfl. as you can see they did just fine. i took 5 more cuttings yesterday into rockwool and 4 out of the 5 have already perked up.
as soon as i have some money to toss around i am going to finish building my cooler cloner though, so dont write off what desert rat is telling you. aero/fog/and bubble cloners work great if you can get them dialed in.