Use a curved needle. Keep your awl perpendicular to the leather surface.
Use a piece of pipe or bar stock clamped in a vice for your anvil, or use an anvil with a horn that is forged as part of the anvil.
I see from your IP address that you are in Excelsior, Minnesota, 55331 so should have access to a Tandy store (or others you can visit or web order from. Tandy has brass rivets with burs, #12 x 3/4" long.
You might like to add your location to your profile so people know what part of the world you live in and can give you meaningful help for your part of the globe.
Tom