For those who don't have time to watch the video...
Step 1: Start with a 25c denomination machine, with no more than 5 lines/credits max.
Start with $100, and play until you lose the $100 or double up to $200.
Step 2: Go up to a $1 denomination machine, single credit.
Set $100 of the $200 aside, and play on the other $100 until you get to $300 or lose that $100 you put in.
If done correctly, you should now have $400.
Step 3: Go up to a $5 denomination machine. Still single credit.
Set $200 aside, and play the other $200 out, until you lose it, or double up to $400.
If done correctly, this takes you up to $600.
Step 4: HIGH LIMIT! Go for a $10 denomination machine.
Set $100 aside, and play the other $500 out, until you lose it, or get a handpay, or at least double the initial $500.
If done correctly, you should have $1,100, or gotten a handpay. Congrats!
If you decide to go further, understand the risks...