Personally, I like to count in the morning, when I am still fresh. I think it is a bad idea to play when you are tired. It can also be good to go at off peak times, when it is easier to find a heads up game. Other patrons at the casino can be sooooo annoying at the blackjack table, when they agonize over the most trivial decisions or get bellicose because of the way you play. Playing heads up is a lot more profitable too, because you can get in so many more rounds per hour.