When you do the first time or two, the system Makes the rule for you.
In Edit Vendor, you can define default accounts to use, for making your own entries. Then the Banking finds the match. It's much faster than working with Banking downloads as there are limited tools there. For instance, you cannot use "Items tab" entries in the Banking feeds.
And the dates are not your Client's dates. That is the date the Bank Processed it; not your client's spending date, unless they only use EFT, ACH and Debit card.