I've got that same tarp and I used to use a ridgeline like the bushcraftnorthwest guy shows on his site. Now I don't. Just attach lines to the grommets that are at end of the center seam. On the equinox tarp that is the short direction (the 8' direction) which some people find a disadvantage of that tarp (I don't mind that much if I'm on the ground, 8' is plenty long. In a hammock it would be another story). Those lines will go to the trees or trekking poles which will support the tarp. If you hang the tarp such that the white grosgrain ribbons hang down (instead of up like the bushcraftnorthwest guy does) then you can tie your headlamp up to use as a light and it will be suspended over your head.

I use 6 lines to pitch that tarp and it took about 50' of cord. You might be able to get away with less I suppose depending on how low to the ground you intend to pitch the tarp. During high winds I put two more lines on to keep the sides from flapping.