There are a limited number of methods available to the homeowner when the task is to join two or more materials together. Screws are great for metal or wood, but won't work with soft materials like leather. Glue could be used to join soft materials, but might not be the best choice for metal or a combination of materials. Pop rivets are your best choice. Pop rivets are available in diameters ranging from .078 inch to ¼ inch, but the common sizes found in local hardware stores are 1/8 inch, 3/16 inch and ¼ inch. Rivets are available with grip ranges up to 1 inch.
Clean all burrs and rough areas away from the area that will be riveted.
Drill one hole through both pieces for each rivet. If possible, clamp the pieces together and drill through both at the same time. If not, use care to drill holes in both pieces that align properly. Use a 1/8-inch bit for a 1/8-inch rivet, a 3/16-inch bit for a 3/16-inch rivet, or a 1/4-inch bit for a 1/4-inch rivet.
Check the length of the rivet in the assembly. Be sure the rivet protrudes far enough to allow proper expansion of the rivet to lock the parts together.
Use the proper mandrel for the rivet and job. The mandrel will unscrew from the tool end to allow one of a different size to be used.
Open the handle of the rivet gun and insert the shank of the rivet through the mandrel.
Squeeze the handles of the rivet gun until the rivet is compressed and the shank breaks off.
Check the fit. If the rivet is not compressed enough, drill it out (use the same drill bit) and install a new rivet.