I only vote on referendums and there only one criteria is relevant: Does this increase (→ no) or decrease (→ yes) the size and power of the state.

Participating in elections does not make sense as you can not vote for the lesser evil as this message can not really be conveyed. The elected politician will always see his victory as having been the better candidate. Low participation however is the better signal as it says I do not waste my time on this circus.