Hook everything back up using your basin wrench and make sure that all water lines are secure and tight. Let everything set for at least one hour before turning the main water supply on, then begin to check for any suspect leaks that may appear to make sure you have done a good job.
If you find that there are leaks then it is most likely you did not put enough putty around the faucet, simply redo the above steps to make sure and ad a little extra putty to the area.
Of course you could always make it easy on yourself and call an expert. We would be happy to help! Our contact details are below.