There is a good map board at the start of the tracks. The two tracks you'll follow to the top of the mountain are shared with walkers. You'll see that you head round the mountain to the right on the Te Ara Ahi trail for a while. There is a good sign where you leave the Te Ara Ahi trail and head up to the top of the mountain. Even if you're a legend you'll end up pushing at least a little of this track which gets quite steep in places. You'll climb about 330 metres. Be sure to stop and take in the sights as you go - especially the cliff with thermal steam rising off it.
There is a forest fire lookout on top of the mountain. If it's manned you'll be welcome to go up into it for a panoramic view over the surrounding forests, lakes, farms and, on a clear day, Mounts Ruapehu and Tongariro, way to the south beyond Lake Taupo.
The way back down is an advanced technical mountain bike trail. It's a wonderful ride - "a seriously sick trail" - intense for the first half with ruts, roots and drops. The second half is fast, flowing and fun. And all the way, traversing the local Jurassic forest. On a fine clear day this is a magical ride.
This description updated by jimcummings, December 2015.