What are the steps to reconcile a business' bank account?

A Bank Reconciliation Statement is a form that allows individuals to compare their personal bank account records to the bank's records of the individual's account balance in order to uncover any possible discrepancies.

So, baseically, get a copy from the bank of the business' bank account and compare that with the financial books that the business keeps of its activities.

This is the way I do them at work:
Start with Bank Balance
Add deposit in Transit (Deposits you have recorded in the business checkbook, but the bank has not yet posted to your account)
Subtract Outstanding Checks (Checks you have recorded in the business checkbook, but have not yet cleared the bank per the bank statement)
The ending amount should equal your book balance. If not, you have missed a transaction somewhere.