Things You’ll Need:
utility knife,sawzall,level,some 2x4's nails, hammer,putty knifes,and spackle
Step 1:
First you want to shop around for the best one to fit your needs. The best type of safes are fire resistant, tamper proof, and have a push button combination lock

Step 2:
Measure the perimeter of the safe. Make a note of this for the final opening

Step 3:
Make a cutout on the wall with a utility knife, This will be 2-3 inches larger than the actual size of the safe.

Step 4:
Cut the studs that are behind the drywall to fit the opening, To make your frame work you will want to attach the 2x4's to the existing studs that you cut. This is accomplished by nailing the top and bottom vertical 2x4's to the studs that you cut from the wall. Try to attach these to additional studs that run vertical behind the opening

Step 5:
The next thing you want to do is measure the safe itself. NOT THE LIP portion but the actual body of the safe.

Step 6:
Put all of the pieces together and make sure they fit around the safe. Nail this frame to the 2x4's that you installed and if need be put shims in all places that show signs of gaps.

Step 7:
fill in the area with pieces of drywall and spackle and paint to match the wall.

Step 8:
Install the safe with hardware provided and you now have a place that is out of the way to keep your valuables