heads up on the end

i have had some trouble with finishing out my tournaments with regards to heads up on the end. i either am against the maniac who goes all in every hand and makes it pure luck or against the slow patient player waiting for you to make a mistake and then pounces. i get impatient which i know i need to work on. any advice to playing against these types of players or links to some threads. i'm sorry i know it's probably been discussed i just wanted to state my specific situation.