Poker Bankroll Management- Starting Small

So back when i started playing in Pokerstars i had my first 10$ in the account. I was playing either SNGs (1 table) or Head-Up SNGs. I took my bankroll to 50$ and then when it dropped to 40$ after a series of bad beats i was so tilted that i took out the rest 40$ of the account and till then i only play freerolls. So lets assume i have 2-3$ on my account. How do i get the proper bankroll management for that? I dont even know the basics of bankroll management regarding 1table SNGs, what is the percentage of my bankroll that i should be getting in an SNG. What should it be when i play a 45players SNG, and what when i play a 90 or a 180 players SNG? What is the result i should be expecting, in regards to profit etc. Thanks in advance!

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