How to fix my iPhone 4 screen?

Half of it is cracked and the glass falls of sometimes. Are there ways of fixing it myself? Or how much would it cost?

Make poop

Easy - Go to iFixit.com (guides and stuff) then go to Accessophone.co.uk and buy a screen and easy all done.

Don't buy from ebay they are the cheap screens they are flimsy and won't work very well I've been using Accessophone screens for a few months and they are brilliant!

IFixit.com