In heads-up there are no more payjumps. You are just trying to win all the chips / money, and therefore there is no difference, if its a cash game, a heads-up SnG or the final phase of something larger like a 9-man SnG or a big MTT. The main difference between heads-up and any other format is, that SB has position postflop. I am sure, plenty of stuff has been writted about heads-up strategy, and I am not an expert in it, so I will not try to post a complete guide here. But needless to say, since you are paying blinds every single hand, you need to play the majority of them, so ranges are wider than in any other format. And you also need to fight more for pots. You cant just sit and wait for the nuts before betting, or fold to every single bet from your opponent. They dont always have it either, since they are also playing like 80% of
hands.