I set the alarm on my cell phone to go off at 10pm every nite, unless I turn it off, I won't forget...that just my 2 cents
edit: Sage had said that there's a +/- 1 hour window....I took my last active pill about 2 hours later than I should have. I've heard everything from 1 hour to 6 hours being safe, reading that post makes me a little worried