Yeah, you definitely want it directly above the center tube for a smoother vape, at or above the side holes on the posts, so that the air is able to flow better around it.
The way I do it, I end up with a leg pointing in both directions off of the side of the wick (kind of a 'Z' shape,) when wrapping the coil. The legs will both be on one side of the wick that way, and I make sure they are on the bottom side when installing it, so that the rest of the coil sits slightly above the post holes that the legs go in. I've also wrapped the legs around the screws at the top (on the Phoenix, a similar rebuildable) before, and that worked pretty well, too.
Try to keep all loops on the coil spaced well, and don't let the legs be too long, to prevent hot spots.
Here's a decent video on rebuilding an A7. It's a little hard to see much detail, but it's not terrible, either:
A7 rebuildable atomizer - YouTube
I know that I'll be trying several different coil setups in this thing, but it'll be awhile before I get around to needing another coil in this.