How do you prepare a bank reconciliation?

What format should I use?

There is no set format as long as you get it done. You just need to put bank and book on separate sides, left and right or top and bottom.

Easiest software is excel spreadsheet. Start with opening balance; add all deposits for month, less all withdrawals and paid checks.any checks not on statement add back to balance, conversely any deposits not on statement delete. After tallying plus and minuses ,net is derived to get ending balance.From the prior month any checks appearing currently and not recorded in prior month reduce ending balance for current month; and any deposits not recorded previously, add to current month's total