Using the monthly statements I receive, I balance my checkbook every month. Sometimes I don't get to balancing it for a few months, but I check my account online frequently throughout each week, in order to monitor activity. I can relate to how tricky it is to keep track of certain transactions, especially those automatic withdrawals and debit card purchases.
When I physically write checks, of course, I always make the entry in my checkbook. As for automatic deposits, well, you usually know when your payday is, so that's easy enough to write in. We have an automatic funds transfer into another higher interest bearing account, and I know that transfers every Wednesday, so that's also predictable. I do find it necessary, though, to keep checking online every couple of days to find those easy to forget transactions, like ATM withdrawals, in order to enter them, too. One system my husband and I use is to make sure we get receipts for everything (ATM withdrawals, deposits made at the bank, or debit and credit purchases) and put them in one designated place in the apartment. I then try to review them and enter those transactions in the checkbook once or twice a week. After I see online that those transactions have shown up in my account, I shred those receipts (except for any I may need for taxes, warranties, returns, etc.).
It's a good idea to have a regular "desk day" every week to take care of your household management. That would be the day you file, act on, or toss papers that have accumulated, clean up that pile of junk mail, and deal with your checkbook. Many people like using Quicken, which enables you to download transactions from your bank online, but you still have a certain amount of personal responsibility in error-checking.
All the best...