I found the best tip is to make sure the white runner cloth is cut to the right lengths. I think the instructions on my headliner were to trim an inch or two in from the end of the bow once you slide it in, but I found that can cause bunching and wrinkling.
What you need to do is slide the bows into the runners and trim the ends of the runners off.
Put the headliner in and attach the hooks in the back, then start working your way forward and put the bows into the holes where they go. They'll be hanging down at this point.
Once all the bows are in place, and the hooks are secured, grab the front of the headliner and pull it forward. All the bows will pop up into place and it'll start to look like a headliner.
Pull the fabric forward and slip it onto the teeth at the top of the windshield to hold it in place, then go to the back and start getting wrinkles out. Like I said, expect to see some bunching and wrinkles where the runner cloth is too long and bunching up. If you see this, grab the fabric where the bunching is and start tugging it down until you hear the runner material tearing. Once you hear it starting to tear, give the cloth a tug towards the side of the car and see if all the wrinkles in that spot are gone. If so do the other side, and if not tear the runner until the wrinkles are gone. Do this for all the bows.
Once the wrinkles are gone, start gluing the sides using contact cement. And for holding the fabric in place while the glue dries I would suggest going to Staples or Office Depot and getting a bunch of those 1/2" black spring paper clips. They're cheap and work great. Once the glue dries, start putting on the back and side trim, and keep looking for any wrinkles that form and if you see any tug on the fabric until they are gone. Then pull the fabric at the front tight, slip it back onto the teeth, and attach the front trim.
Trim off the excess material, reinstall the dome light, and that should be it.
