When twisting wire, you will get some differences in resistance depending on how tightly you twist, etc.
Twist up some 28G x 2 and 28G x 3 strands. You don't need a drill. You can use a coffee cup. Some good YouTube videos on doing this with a coffee cup, a pen, etc.
Decide whether you're going to use 2.5, 3mm, etc and spin you up a 6 or 7 wrap coil with both the 28G x 2 and 28G x 3. Not sure of the deck on the Berserker myself, a 3mm might be too large? Maybe start with a 2.5mm.
If you're using a regulated mod, the resistance isn't that important, just tweak your wattage until you get a vape you like.
I've used 28G x 2 and x 3, 6-7 wraps and can get a great vape from either one of them. Just play with the wattage. I enjoy twisted kanthal myself, just been playing with a lot of other wires/builds lately.
Enjoy your new RDA.