Don't risk having your kitten get out of the house and wandering away without proper identification. Introduce a breakaway collar with an ID tag from the first day he's home, and your kitten will grow up thinking a collar is perfectly comfortable and normal.
Start when your kitten is already relaxed. Put the collar on, giving praise, treats and physical affection for a minute or so. Then take off the collar and walk away so there is a dramatic drop in attention. Do this a couple times a day for a week, and then in the second week, add the collar when your kitten is being fed. When he wears the collar without issue during meals, start leaving it on for longer periods until your kitten is permanently collared.
Animal behavior experts Susan and Roland Tripp are the authors of "On Good Behavior." For more information, visit their Web site at AnimalBehavior.net.