40 minuten - 1 uur
My little sister left her iPhone on top of her care being in a hurry one day. She's usually keeps her iPhones in very good shape. But this time it slide right off the top of her car and shattered the screen pretty bad. It was still responsive to touch and the front facing camera, sensors, and home button still worked just fine. She overnighted a screen to her house because I was coming in town to visit for the weekend.
The repair went better than expected. But, Wow! Those screws are super tiny. I've seen salt crystals larger than those screws. Fortunately I have somewhat skinny hands and fingers. I just carefully laid out every piece and screw that was removed in the orientation that they were in the phone so I didn't have to take a picture after every move. Well, I didn't run into any issues at all. Took me about 30 minutes from start to finish and her iPhone powered on and worked perfectly on the first attempt. Pretty %#*@ impressed with myself actually. So was everyone else. ;-)
The only real advice would be to take your time (obviously) and to immediately take a 30 second break if/when you feel yourself getting "shaky" or nervous. I was sipping on a nice beer the whole time and probably took about 3 or 4 little breaks during the process. I think it helped a lot personally.