I have the same clone and I've found 1.5 to 1.7 to be the best for me. I use cotton. I tried the cotton yarn but could never really make it work so went to cotton ball and works much better. I just build a standard horizontal coil and once it's tightened down i turn it so that its openings are away from the screws. Put the chimney on, cut the wick about a centimeter above the chimney and tuck the two ends down around the liquid channels.