No one watches my videos after all.....
in my hh 101 (video section or YouTube) I attach a length of paracord between the two o rings on the tarp and use a prussik knot to make that length tight. That means you can hang it in the normal standard method but it gives the effect of hanging with two ridge lines. When I get in the hammock it obviously sinks a little but the tarp stays in place because it isn't resting on the hug net, it's usually about nine inches or so above the hammock itself.
With the prussik knot on the paracord you have abit of freedom with it's height.
During bad weather this helps as well because when you peg the tarp down at more of an angle, there is still a gap along the top for ventilation!
I'll repost my video just in case: