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With my radio (JR). I assign channel 2 as left aileron, I assign channel 6 as right aileron. Just like you do on a real plane. Then I turn on the flaperons/spoilerons. This might be different with your radio. Check your radio manual for flaperon/spoileron settings and assignments.

If you know how to adjust all the settings on your real plane for spoilerons and flaperons, this is going to be a piece of cake. If you have to learn it ... well, you have to read your computer radio manual.