Check List.

Swimming
Tri suit, Wristwatch, Goggles + backup pair
Swim cap from race bag + backup cap, Wet suit, Timing chip neoprene band (optional), Ear plugs (optional), Nose plugs (optional)
Biking
Bicycle with bike number attached, Bike helmet, Bike shoes
Bike pump, Spare tire kit, Water bottle or Camelback, Socks
Sunglasses, Bike gloves (optional)
Running
Running Shoes, Race belt with number attached
Transition Area
Towel, Gel / Power Bar / Other nutrition; may want to tape these to your bike,
Extra water bottle, Body glide, Lip balm, Sunscreen, Bike tools, Large pump