In addition to your snowshoes, here are a few suggestions to consider for your next Snowshoeing trek:
Check the weather before you go on especially long treks
Poles - to help steady your walk through the snow and keep your balance
Waterproof and Insulated boots - choose boots that will keep your feet warm and dry. Adjust the binding to your boots before going out in the deep snow.
Socks - merino wool socks are comfortable in cool or warm conditions, absorbs and wicks moisture, cushions and doesn't itch like ragg wool. Some synthetic materials have been designed to be comfortable and wick away moisture but are less expensive than wool.
Gaiters - These can be helpful to keep your pants dry and snow out of your boots if you are not using waterproof winter sport pants.
Gloves or mittens
Hat or balaclava - Balaclavas are especially useful when there is a lot of wind
Backpack - useful to carry snacks and/or water or other emergency supplies if you are out longer than you expect, i.e., spare gloves or socks. Some back packs have provisions to contain a vacuum bottle for hot liquids.
Scarf or neck gaiter - especially helpful on windy days
Hand and toe warmers - good for long treks of several hours and are fairly inexpensive. Many brands last 8 hours or so.
Fully charged cell phone
Layered clothing - Snowshoeing can be strenuous at times so it is important to dress in layers that won't trap moisture