Not buying the cheapest tires. Which usually turn out to be that. Your local Michelin dealer can help. Also find out if there's a warranty plan available. Don't overlook looking at the tires.
Cosmetics are an important criteria.
This is so you can be notified of any product updates. Anyone who follows these basic guidelines is ahead of the game when shopping for tires and most importantly will end up with a set of tires that will keep them driving comfortably for years.