If we were playing a MTT and find that we were fortunate enough to be one of the final two left, then we can be assured that both players are probably competent and neither has a skill advantage. This means it will come down to the deck. The game will more than likely get solved when KK runs into AA or some other big hand vs. big hand. At this point it is out of our control.
If we are playing a HU format (rather than a MTT or SNG), then the skill edge may be a bit wider, so we will need a good HU strategy to succeed. For me, my strategy is fairly straightforward, and I feel like I am fairly competent here as my bb/100 is 3x higher than my full ring bb/100. Maybe some of you can bounce this off of your stats and let us know what a good HU bb/100 value might be.
Pre-flop, when OOP, I will simply call the BTN to get to a flop when I want to play the hand. When IP, I will almost always make a bet because I will have the positional advantage on the flop. Initially I will vary this bet size until I can deduce which bet sizes may get more folds. When I know this, I will likely use this bet size with my worse hands and the smaller bet sizes with my better hands, but obviously we need to mix it up. My pre-flop all-in requirements are quite high - medium/big Aces or pocket pairs. I will not go all-in pre-flop without some showdown value already in hand. If my opponent wants to shove to win a couple bb's, then let him.
Post-flop, I will maintain pressure when IP, and will play passively OOP. Since we are playing HU against almost any 2 cards, the board texture is less relevant than when we know we are up against a 20% range. Did we catch a piece or not, becomes hard to really know? We will find out quickly if our opponent caught a piece, when the betting/calling/folding starts.
Our opponent is still important and we need to pay close attention to their aggression level and their frequencies/ranges. But with only a single player to watch, this is very easy to do. While
bluffing is still a thing HU, I believe that the game is now more value based rather than aggression based. We must win that last hand and we can only win it at a showdown, and we will not win it bluffing.
Good luck and God Bless.