1) Foam- I used camping foam. (Can be bought at Walmart, $9 for a 20" by 72" roll. Needs to have a half inch thickness.
2) Craft Knife- I use a Stanley. Buy a quality one if don't already own one.
3) Duct Tape- Good old duct tape. I used the Gorilla version because you can buy it in different widths.
4) Phone- I have an iPhone but it can work with any brand.
Step 1: Getting the Shape of the Case
Trace your phone out onto the foam. (I used a sharpie). Draw a box around your phone approximately 2 to 3 inches from the sides of the phone. Cut the larger rectangle out. Then cut the smaller rectangle (or whatever the shape of your phone is) out, leaving the corners in so that the phone will stay in the case. (See pic 1) This will be your top layer.
Using the top layer as a stencil, trace it out on another piece of foam. Cut that out as well. You may want to cut a hole in the bottom so that the speakers work. (See pic two)
Now cut out a rectangle of the same size as the first two but without cutting a hole for the phone put the phone in the center of the third layer and cut out a hole for the camera. (See pic 3) Make sure the camera still can see by opening it with the phone in the center of the piece. This will be your third layer
Step 2: Putting the Case Together and Tweaking It
First, take some duct tape and put it all around the second and third layers. Once they are firmly together, ad the first layer on top and duct tape it to the rest.
You may want to cut out a place for the home button. I made mine in such a way that the finger reader can still works since I have an iPhone 5s. (See pic 1)
If you phone will not stay in, try hot glueing small pieces of foam into the corners of the top layer.
If your phone has a "selfie" camera, it is quite simple to cut a hole for that. (See pic 2)
CONGRATULATIONS! The next time you play football, you can just use your phone!
WARNING: This case is not invincible. Things that may harm you phone while in this case are: Bullets, Fire, Water, Axes, Knives, Raging Mothers, Determined Hamsters, Missiles, Hammers, and Extreme Temperatures. BUT NOT GRAVITY!!!!! MUHAHAHAHAAAA!!!
*I am not responsible for the Health of your phone.