you could do ir by simply getting a ir kit and connecting to a relay and then to your wall switch.
another way is connection through a home alarm system with a relay module.
another way could be through your ocmputer with a network relay switch wired to the wall switch of your garage door.
another probably simplest way would be with an IOBridge and the app available in the app store. This way you could actually open the door if you were on the wifi or on your phones data. so you could even open/close the door from elsewhere. Ive done this for office building access doors.
I can explain it for you but I cant understand it for you
I won the World Poker Championship in 2010 with Pokemon cards