Warm and dry down below
Please do not wear jeans, because once they get wet, they stay wet! There are great functional pants with stretch fabric that are comfortable, breathable, and keep you warm. They often have elastic at the bottom of the legs that goes over your shoes to prevent snow from getting in. Gaiters also help here. Wet, cold feet should be avoided at all costs.
Snowshoes can be easily strapped onto any sturdy footwear. Your winter boots should be at least ankle-high, waterproof, warm, and sturdy. After all, you'll be walking in the snow.
Extra tips from the pros
Always bring 2 pairs of gloves and 2 hats! One pair of thin gloves for the ascent and one pair of warm gloves or mittens for the descent. The same principle applies to your head. When exerting yourself, a headband or thin hat is ideal, but during breaks and the descent, be sure to keep your head warm, either with a thick hat or a warm hood. Sunglasses help protect your eyes from the glare of the snow. When buying sunglasses, make sure they have UVA/UVB filters! Speaking of UVA/UVB filters: apply sunscreen. You can still get sunburned in winter, especially when you're out in the snow, which reflects the sun's rays!