Clothing/Shoes/Weather Gear: Depending on the season you go to Waterton, know that because its in the mountains, the snow takes a little longer to melt, and its a little chillier, especially at nights. Bring clothes you can layer, and that are windproof. The winds in Waterton are anywhere from 60km / hr to 100km / hr, on average!
Waterton Lakes National Park can be very warm during the day and freezing at night. A warm jacket, gloves and weather proof shoes are a must.
Toiletries and Medical Supplies: Pack light, everything is readily available
Photo Equipment: I always travel with my Minolta SLR camera with 2 lenses (1x 35/80 and 1x 75/300 zoom), a two times converter, a polariser for both lenses, a spare battery and 10 spare rolls of 400 asa film with 1 loaded in the camera.