How to program flaps for a plane?

Im getting ready to program a plane into my devo12s w/deviation. It will have two seperate aileron servos, so i figured i'll play with mixing some flaps into the ailerons. But, i have no idea how to do this. (I'm really a heli guy).

I was hopeing to use one of the extra trim tabs as the control for the flaps, giving me different degrees of flaps added.

It would also be nice if i could set up a % box so i can see how much flaps has been set.

Hi Kdean,
try to put the left or right Key (it´s your free choice) above the "trimmers"
as switch.
But i dont know exactly how you must do this.

.... see my signature...

greetings
Raimund