in a cash game i would i don't bluff too much and i don't like playing heads much at all. but in the tournament i'll raise most every blind and try to keep chipping up slowly until i can get a hand worth an all in or spike trips/straight on the flop and then it's over.
for me, it depends on how many chips I have in both situations. if I have the chip lead in either situation, im going to be very aggressive.if not, I would have to feel out my opponents and the cards and go from there.
Not sure what you mean by heads up in a cash game.
Everyone folds except you and one other player.... just play normal.
Table is empty except you and one other player... I play loose/passive.
The blinds aren't changeing. Since it is just you and one other the odds are better when you get a face card or connectors.
Tourney I assume it is final table heads up... play loose agressive. For the reason stated above plus sense of urgency due to blind increasing. SB I call/fold while BB I call/raise. Depends on my cards and how the other player plays.
The general strategy of the game heads up:
1. A or K with any card - very strong hands that need to be played aggressively.
2. Hands with J or Q are sufficient for a minimum raise preflop.
3. Any pair will be stronger than your opponent's hand in most cases.
4. The top pair on the flop is a strong hand. Do not worry about the kicker: losing the kicker with the top pair - the situation is rare.