If you manage to keep these guide lines it reassures that you are able to stay alive as long as possible. You will play in games that you can afford. You will never play in games that are above your head because when you're losing, you'll have no choice but to drop down to a smaller game. You are able to sharpen up your game at the lower limits until your bankroll allows you to move up and take another shot. Whilst following these rules you also prevent being completely decimated by a bad run of cards.
If you lose you need to go down in limits in order to not risk losing a massive amount of your bankroll, or even your whole bankroll. If this would occur you will need to fight a even greater fight on your way back. Keep this in mind as motivation. Keep the discipline and you will be successful.
Good luck at the tables!