I'm bored, so I'm changing my type to whatever you want it to be! You can base your decision on whatever you want it to be on, examples:
-I just got into a fight with an ISTJ today, and I don't like the OP, he makes me want to change his type to ISTJ so I can always loathe him
-I'm sick of iNtuitives, I want this person to be a sensor
-I love my type, he will also love my type.... if he doesn't then
I'm lookin forward to the results...