Started doing that this month after I lost my entire limit bankroll due to tilt and tournaments(which I suck at). Hadn't played no-limit and used up all the money in my account to the last dollar. If you want to build up your BR fast do what I did. Play until you have 10 buy ins for your current level + 1 for the next level up. If you lose that 1 buy in then just drop back down and get another:
<$25 1c/2c
$25-60 2c/5c
60-125 5c/10c
125-300 10c-25c
I am taking shots at NL$50 atm but am having some trouble.