i would wait till you are about to turn over to flower before you take clones
the older the plant are the more stable the cutting should be up to about 6 weeks in veg
and its always good to lol pop the plant a little ( even if its just a couple of stems and fan leaves at the base of the plants) just before flower as it help with air flow
and watering of the plants
domes
you don't have to bye one, just cut some plastic bottle into domes shapes and you should get 4 clones in each one in small pots of soil or rock wall cubes
don't put them under hps and if you have no over light keep the light 4 ft above the clones but a t5 would be best
change the air in the domes every day and keep the soil/rock wall damp for the first 4 days and them dry them out a little more to encourage the roots to look for water
but check them every 12hours and you should see roots in 7-10 days and then it time to re pot