Approach via the meadow. While there, take a gander at the imposing face. See the big, right-facing dihedral on the left side of the face? That's Great Arch (5.5*)
. See the smaller, less-obvious, left-facing flake that doesn't go all the way to the top to the right of Arch? That's No Alternative.
Get to the ledge partway up the rock by one of the standard routes. See the Great Arch
page for two popular alternatives.
Once on the ledge, traverse right as far as you can. You'll be standing under an obvious left-facing flake; this is Pitch 1 (5.4) of No Alternative. A 50 meter rope won't get you all the way from the ledge to the top of the flake and you may have to set up an intermediate bellay. A 60 meter rope might do it, but it will be tight. The flake takes gear like nobody's business and you'll have many opportunities to stray right onto the flake itself. Eventually the flake ends at a small alcove with a tree and a pair of bolts.
Now the real fun begins. See that bolt directly above you about 80' out on the horizon? That's the route and that's the only pro you'll get. Use your momentum, thank whatever dieties you believe in for sticky rubber, and head straight for that bolt. Don't bother farting around with other pro as there really isn't any that's worth falling on. Clip the bolt and keep going another 50' or so to the bellay station (pair of bolts). The final pitch is similar in character but less steep and not as long. Top out from the second pair of bolts in whatever manner you feel appropriate; a belay might be appropriate until you're really in walking territory.
This is a popular and long route. Please walk down via the west-side hiking trail rather than rapping down.
Bring a small rack of trad gear for the first few pitches. For the last two you'll need a couple slings and biners. 50 meter ropes are essential but longer would let you string together the flake pitches.