If you do a yahoo search you will find all the details, but I will summarize what I do.
Put a rough mechanical setup on your bow (level nocking point, eyeball the centershot by splitting the riser with the string and adjusting the rest inline)
Get close to the target - 10 yds if you're brave.
Shoot a group of 3 normal fletched arrows aimed dead on center ( don't worry if the group is off center yet). Now, without adjusting your aiming point, try to shoot a bare shaft (normal point, normal nock - no fletching) into the group.
Tune vertical offset first. If the bareshaft shoots higher than your fletched group, raise your nocking point or lower your rest. If the bareshaft shoots lower than the fletched group, lower your nocking point or raise your rest.
Repeat until the bareshaft is on the same horizontal plane as your fletched group.
Still at 10 yds, tune horizontal offset. If the bareshaft is left of the fletched group, move your rest to the right. If the bareshaft is right of the fletched group, move your rest to the left. Repeat until the bareshaft is on the same vertical plane as your fletched group.
Now you have a rough tune. I usually adjust my sights at this point, because additional tuning is on a much finer scale after this step.
Now move back to 20 yds, and repeat. Fire the 3 arrow fletched group, follow up with the bareshaft. Even though we were decent with the 10 yd tune, we can really dial it in now at 20. Tiny adjustments will bring the bareshaft back into the fletched group.
I usually realign my sights (if required) and walk back again to 30 yds, and repeat. From this far, you can see the bareshaft in flight, and it always amazes me that an unfletched arrow can fly so straight! (Of course, a bare shaft probably wouldn't flyso good with a broadhead on it!)
Which brings me to my final tuning step. Even with a bow tuned to shoot bareshafts with fletched arrows to 30 yds, what matters is our broadhead tipped arrows. I do the same walk back tuning with fletched broadheads, eventually refining the tune on the bow so that broadheaded arrows shoot with fieldpoints to 30 yds.
Hope that helps.