IMO focus and common sense is far better that tying yourself to a wrist bracelet. What happens if you forget to use it?
As has been mentioned, just get in the habit of touching your case first. Also, save those anti-static bags to lay things on when assembling MB parts, HDD rails, etc, before putting them in the case.
Also, avoid doing it on carpet if possible. There's more chance for static and dust. I have carpet in my living room, but always do my assembly in my kitchen under a bright florescent light while standing on linoleum.
One option I highly recommend which I've found to be useful is taking your fans out first when they're brand new and giving the inside of their housing and the fan blades a light coat of ArmorAll. Just a small amount rubbed into the plastic thoroughly, then wiped dry, keeps them very slick and more resistant to dust clinging. The dust will blow or wipe off a LOT easier.
MAKE SURE you spray a small amount on a rag, NOT on the fans. One little spot on the corner of a rag, then rubbed into it so it won't drip. This takes a little while but is not hard when parts are new and clean, and can save a lot of tough cleaning on down the road.