ICM: Some general rules?

[DonLigretto]

Hi

I'm giving 4tabling 6$ turbos a shot once again, since now I have quite a healthy BR of about 650 bucks. So far I still suck in my opinion. So far I played about 20, finished about 10 times 2nd, the rest 4th I guess 8 times and twice 7th or 8th.

I'm analyzing all my games with SNGWizard however still don't quite understand what I'm doing wrong. So far as I see I play pretty good until we're down to 4 handed. Could you outline some general rules for these situations since I really really just don't understand whats the correct strategy on the bubble, when you're just 3 players and in Headsup. I guess in Headsup you're pushing really any two cards no matter if Bigstack or Smallstack...when you're 3handed no clue, but at that point I'm just happy to survive the Bubble anyway. But what do you do on the Bubble? I probably tighten up too much I don't know but what do you do as a) small stack b) middle stack and c) big stack when you have i.e. 5000 chips and blinds are at 150/300 and everybody else has about 3000 chips? According to the 10BB rule ICM isn't important here as Bigstack or is it?

I just don't know how I should play in these situations and I would be really really grateful for any hints.