Fixed line set up

I have some routes I'm going to be working on fixed lines this winter.
The scenario:
I have to build an anchor on top of the cliff, rappel over the edge then build my primary anchor that will be the load-bearing anchor while I work the route. I have a method for fixing the rope to this primary anchor that I like, but I was wondering how other people fix a mid-point of their rope to an anchor like this?
Looking for a brilliant, epiphany method that's just amazing!

Shit, I'm probably gonna die.

If its a two bolt anchor

1.) Alpine butter fly one bolt, clove the other
2.) Bowline on a bite

Best is 2 ropes, easier to transfer one to the other then passing the knot.
I use a double figure 8, easy to equalize, strong, easy to untie.
animatedknots.com/fig8loopd…
I would guess you are doing the second anchor due to edges, angles, and such?