Hi multi,That's a very good question and a very important one for many players.The first thing to look at is your willingness to move down.  As long as you're willing to move down, the following advice is applicable, otherwise you need to look at why you refuse to move down or don't move down when you should (a whole different set of advice).Once you know you can move down at will (a great characteristic to have), look at what buyin level you are at and how much lower you can actually go.  If you're at the $5s, you may not want to move down to the $2s because the rake is a higher % of the buyin.  But if you're at $55, you can move down to $33 then to $22 if you keep struggling and even down to $11 and $6 if you have to.  So there's more room to move down.This all leads me to believe that you should move down a bit more quickly when you're playing a lower level and have less levels to move down in.So if you take a shot at the $10 level with 20 buyins, or $200, I would probably move down after losing a net of 5 buyins (or ~$50 dollars), that leaves you with 30 buyins at the $5 level. You can even be a bit more conservative about it, taking your shot at 25 buyins ($250) and moving down once you hit $200 (40 buyins for the $5s).As you move up in levels, feel free to be more aggressive, particularly if your results are good and your confidence is high (these two things are often intertwined, especially if you're not as experienced in the game).  The reason I say you should move up more liberally at those times is because you're often playing best when confident, so your edge is greater.So if you get to say a bankroll of $900, you may consider taking a shot at the $50 level if you've been having good success.  That's only 18 buyins, but you could take a 3 buyin shot, if you lose $150 you're down to $750 and still have 25 buyins in the $30s and still plenty of room to drop down some more if things take a turn for the worst.In the end, be comfortable with whatever you are doing, but if your comfort zone is really extreme (say 150 buyins) you should take a look at why you feel the way you do and perhaps make some changes so that you're more in line with what is commonly referred to as "optimal" or more near "optimal."  But don't switch into a strategy you're not comfortable with, you have to be comfortable before you switch into it or things are too likely to go bad/frustrated you and cloud your more important thoughts (and gameplay).