How to get cracked screen off?

I found out about you on MacPowerUsers... but not until I bought screen, plastic device for prying and adhesive for from another company. Thought I could take screen off by prying. Nope. Have been waiting for suction cup from other supplier for WAY TOO LONG (I'm sure it's lost in the mail.)

but now I found you and your instructions. I fear my screen may be too cracked for suction cup anyway. ?? How do I do the tape thing?

I tried rolling up a piece of gorrilla tape, it didn't hold at all.

Thanks for help.