take a day or several days off, even that may not work. I lost 3 SnG's in a row to come in 4th to horrendous bad beats ( in the 3rd someone pushed all in on a steal into my BB with J,2, I had AA & he caught 2 pair ) I've found that bad beats come in bunches & its just best to stop playing. After those 3 in a row I quit for the day, did some chores & played some counter strike.
The next day I fire up a new SnG very 1st hand I'm delt QQ in the BB, instead of feeling happy about my great hand I get a feeling of dread. A few limpers & 1 re raise before me, I make it 200 to go ( starting stacks are 1000 ) I get 1 caller. The flop comes 6, 8, 10 rainbow I lead out with a 300 bet & get check raised all-in. I call & villan shows 7,9 of course. I'm out very 1st hand & I'm now right back into tilt mode.
I'm now taking a week off from online poker, when I'm playing on tilt even if I'm playing well I NEVER win. When you go into a hand expecting someone to catch a miracle flop to beat you I find that 9 times out of 10 they will do just that.