Replacement Screens Never Glue Evenly

As the title, I have repaired quite a few phones now, but I always struggle to glue the screen evenly down on all sides. Most of the time there is a gap large enough to fit my finger nail down. At best, the screen is glued down evenly but there are ugly large clumps of glue between the frame and screen which are hard to get rid of.

At the moment I apply B-7000 to the frame of the phone, then put the screen down before clamping it down with 12 QianLi clamps - 1 on each corner, then 8 in the middle. I don't put anything between the screen, clamps and back. After leaving for around 12 hours I look at the phone and clean off any excess glue and sure enough there are some portions of the screen sticking up.

Do you guys have any tips? How do you glue your phone screens down evenly?

Edit: I'm talking about doing screen only repairs on Android.