3 effects two flipper switches question

[jimilee]

I'm working on a multi effect with 2 flipper switches and 3 effects. How can I wire in the third effect to the flipper?

[mauman]

With two switches and three effects, you can have the following four combinations.  Call the effects A, B and C.
B only
A + B
C only
A + C
You'll always have at least one effect on (B or C) and A can only be run in combination with B or C.   To have more combinations, including A only, B+C, or or all effects off (bypass) you'll need three switches.