Start with about 20 buyins at 2nl or 5nl. This means either $40 or $100. Now,
don't put anymore money into your poker account ever. Instead,
grind through the limits and get good at poker. Then, the higher you get, take a slightly higher
bankroll requirement than the stakes previous so that you better protect your poker
bankroll.
When you have $100, play 5nl. (20 buy-ins)
When you have $250, play 10nl. (25 buy-ins)
When you have $750, play 25nl. (30 buy-ins)
When you have $1750, play 50nl. (35 buy-ins)
When you have $4000, play 100nl. (40 buy-ins)
When you have $10000, play 200nl. (50 buy-ins)
If you follow this and regularly play and work on your game, you'll be making a lot of money in less than two years
imo.