Straight up the path from fitz park. You contour a bit to the right to get to the summit. Back down to the gate, run a bit further then just cut to the right which just really cuts the path off.
Rejoin the path, through the gate and back down to fitz park.
Beware though.

The route isnt a problem but post race blisters will be if your feet are not hardened. You can do it in road shoes but if they are a tad big you will get blisters. To small and black toenails will follow.
First year i did it i had blisters for about 3 weeks after.
Great race though, tough one if its really hot.

Good luck