just break it into chunks and run within yourself - that's the hardest part. it seems strange to run slowly across a stretch of ground you know you would normally cover at a much faster pace.

in my first ultra (high peak 40) i ran the first 6 miles in 1 hour and at such a pace that i felt like i'd done nothing at all. coupled with a refuelling stop, i pretty much reset myself back to zero at CP1 after which it was only a 34 mile race, and so on to the next CP, so on and so forth.

also - walk the hills and run the flats! define your goal before you start - just looking to finish or aiming for a particular time? i'd suggest just finishing your first ultra will be enough of an achievement. you'll then have a benchmark for next time round because i guarantee you'll be hooked!!

good luck!