Making a glass guitar slide is quick and easy when you have a handy dandy mill file,
And some pizza, oh, beer too, You need that, or any glass bottle really.
Step 1: Supplies
You need a Mill File and a glass bottle, any will do, but with beer, it makes the time pass by quicker.
Also, You will need some food too, pizza is the best choice, goes good with making things.
You might want to put in a good movie or some awesome music as well.