The reason I make it sound hard is, for me, it proved to be next to impossible to get it right enough times for me to build even a single coil alien at 7 wraps, 3mm ID, 28g Ni80 / 38g Ni80. Whereas without using any sliders at all, it really is easy as pie as long as all the prep work is done right and the drill is sped up to maximum speed after watching the alien wrap catch... so IME the no sliders method is both easier and faster.
For the SSFC coil build, I use a (semi) flat key ring that's about 1 inch in diameter, with masking tape attached to it between the spaced claptons and it. The masking tape acts like a cushion, and, it also provides additional grip on the wires so the key ring doesn't as easily tend to slide off of the spaced claptons. Each time when I move the key ring I gently pull open the key ring to relieve its pressure from the wires before I put its pressure back on again so the key ring doesn't grab the spaced wraps at all. My key ring doesn't apply too much pressure on the spaced claptons because my key ring has been loosened up a little bit. I put it on in such a way that it feels comfortable to work with, and the center of gravity of the key ring is lined up with the wires so the key ring doesn't swing around. If your key ring applies enough pressure on the wires only at the drill side of the key ring, then, at the swivel side of the key ring, you can actually even wrap two small pieces of masking tape around the key ring (one piece on each side of the wires) to prevent the swivel side of the key ring from moving too much. (I found this technique works particularly well for staple coil builds, as the key ring will gently wobble itself towards the swivel so, with a staple coil build, you don't even have to stop the drill and move the key ring.) If you don't have a suitable key ring that can be used to make an SSFC coil build, then mini clothespins also can work.
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