Preflop Guidelines

Preflop you can come in with the worst hand but because of the extra blinds in the pot (and especially antes) you don't need to win 50% of the time after the flop. Add in the ability to exploitation and you can play a lot of hands. OR you can come in with a hand range that has a 50% chance of being best and fight to split the blinds or better. Or you can play tighter than that and play aggressively to reduce any error you might have after the flop, and err on the side of aggression but still be cautious after a couple bets. Or you can play extremely tight and always bet and be much more aggressive representing aces.

I have outlined the 3 strategies by probability hand range is best for 6 handed and 9 handed play.

6 handed chart
		% chance of having the best hand preflop
	plys left	0.4	0.5	0.6	0.75
UTG	5	0.1675	0.13	0.097	0.056
UTG+1	4	0.2205	0.159	0.12	0.069
Cutoff	3	0.2632	0.206	0.157	0.091
Button	2	0.3675	0.293	0.225	0.134
SB	1	0.6	0.5	0.4	0.25
9 handed chart	plys left	0.4	0.5	0.6	0.75
UTG	8	0.1082	0.083	0.062	0.035
UTG+1	7	0.1227	0.094	0.07	0.04
UTG+2	6	0.1416	0.109	0.082	0.047
Lojack	5	0.1675	0.13	0.097	0.056
Hijack	4	0.2205	0.159	0.12	0.069
Cutoff	3	0.2632	0.206	0.157	0.091
Button	2	0.3675	0.293	0.225	0.134
SB	1	0.6	0.5	0.4	0.25

1)Play a better hand against more difficult opponents.
2)Play a better hand against looser opponents that will call you all the way down but also see a flop with more hands. BUT you also might limp in with some hands that are weaker to see a cheap flop against loose players hoping to hit a flop.
3)Play a worse hand against loose preflop opponents who are trying to hit a flop if you can bet and take down the pot and also against tight players who are tight after the flop. Also play looser if you feel opponent play tight and won't be able to let go of a big preflop hand if you hit the right flop.
4)If your chipstack is deeper relative to the size of the pot, you can play a lot more hands. If the chipstacks are short you want to play a much better hand. This is because of "implied odds" and if you hit a big flop you have a deep enough stack to get paid off.
5)Think about how you will respond postflop. This should govern your strategy before the flop as well.
For guidelines on what these hands actually mean check out this post.