Not voting at all. Christians say that they are in the world but not of the world so why do they feel the need to vote at all? The Bible says: Thou shalt not follow a multitude to do evil (Exodus 23:2). All the candidates are evil. Voting for the lesser of four or three or two evils is still voting for evil. I will be staying home on general election day just like I stayed home on primary election day.
If you want to vote then go ahead. But after the results come in, subtract your vote from the total your presidential candidate received and see if it makes any difference.