The way I bend thin metal (like yours) without a press or a brake, is using a bottle jack against a hard surface (frame rails of jeep, trailer hitch, etc.). Get a bottle jack, or a floor jack, and a piece of wood that is the same angle you'd like to bend the metal, place wood on top of jack and then place metal on top of wood. Pump up the jack until the metal bends to your specifications. You may have to adjust several times and take it slow.

Other than this you'd have to carry it to a shop and ask them to bend it.