from Banqiao station, the 307 goes right by there, but you also have to be careful you get on the 307 going in the right direction. Catch it at the first platform as soon as you exit the MRT. If you catch the 307 on the second (or third?) platform then it will be going in the wrong direction (north).
Get off the 307 right after you pass the gas station on the right/big newly renovated police station on the left.