BTW, you can probably find better yields and larger maximums here: Kasasa.com
What I do is carefully follow the statement cycles. I write them on an envelope (4/25-5/24, 5/25-6/24, etc...), then place a checkmark next to the statement cycle after each purchase along with the receipt. When I reach 12, I stop until the next statement cycle. I then keep verifying with the online statement to make sure I am on track.
I don't think "less than a dollar" is realistic. Just use the debit card for smaller purchases (maybe <$10). It's not going to cost you that much in points you would otherwise earn on other cards.