How to set up spoilerons in G3.5
 

I have just started using G3.5 and don't have a clue as how to mix functions and assign the mix to a switch on the G3.5 controller. I guess the instructions don't make much sense to me yet. I figure after I have set up something like spoilerons on the Yak 54 3D, all mixing and switch assignments should be apparent.

Thanks in advance
Greg