This is the double column version of the lark's head based single column. It starts the same way:
At this point, instead of hitching off the cuff, wrap all the way around the back of the cuff, going between the columns:
Adjusting the tension on this cinching wrap is what determines the overall snugness of the cuff:
At this point, there are several ways to finish it off. One is to split the lines around the front of the cuff and tie a square knot; that doesn't require much space between the columns, but had the disadvantage of only pulling on the back of the cuff, which can make it feel like it's tightening under tension. An alternate approach is to now hitch off the front of the cuff, similar to the single-column version, by first passing through the starting doubled-rope bight:
Then forming your hitch about the opposite half of the front of the cuff:
This will pull on the front and back of the cuff evenly, which is generally more comfortable. You'll notice, however, that it's not symmetrical; if you have room, you can solve that by taking an extra hitch, on the opposite (here, lower) side of the cinching wraps. If you're going to use two hitches, you don't need to first pass through the bight, and done right you will wind up with a clove hitch about the front of the cuff, with half the knot on either side of the cinching wrap(s).