All you really need is a steady heat source of around 200F. I use a griddle, similar to this
Most people have one of these laying around in a cabinet.
Get on eBay and find the digitizer for the phone and some LOCA UV Adhesive. 10ML is way more than enough.
Take the phone apart, then lay the LCD/Digitizer face down on that griddle and let it sit for about 10 minutes. Use a razor blade to VERY CAREFULLY and slowly peel the glass back. You should see the glass separating from the LCD. Continue this and take your time until all of the glass is removed. Then clean the LCD. It takes some work, this glue is extremely sticky and the only thing I've found to completely remove it is Clorox Surface wipes. They're the kind that come presoaked with some kind of cleaner. Even those take a little elbow grease to completely remove the glue from the LCD surface. It should be shiny. A couple specs wont matter, the LOCA has proven to be great at hiding imperfections. Next you will remove the LCD from the frame of the phone. There will be some connectors following through the bottom half of the phone to the PCB that has the charging port on it. Once the LCD is removed, add a line of LOCA glue to the LCD about as wide as a cigarette. Lay your new glass down on that glue, being careful not to trap too many bubbles. If you have a couple, no problem. You can leave them if it doesn't bother you, or you can push them to the edges. Next, align the LCD with the handy little lines that are printed on the back of the glass. Get something to hold it together, clothespins or hair clamps will do fine. After clamping, once again ensure the glass is aligned properly with the LCD. Then all you have to do is take it outside, let it cure in the sun for about 5 minutes, clean the extra glue up and reassemble the phone!!! I've got one waiting for a glass to come in so as soon as I get that I'll try to post some pics. Enjoy the savings, and the adventure!