now you have to heat up the screen using a heat gun or hairdryer.
use a spudger and "peel" or "slide" the spudger under the digitizer, watch out for the lcd screen). Once you're under the digitizer use credit card or plastic cards to slide between the adhesive and the digitizer. if the adhesive is still to hard , heat again.
The guys of smartfastfix ( youtube) link : https://www.youtube.com/watch?v=QLNTUO-f... did a well job on this.