It can be both very warm and chilly in October in the mountains. Layers are your best frisnd. Bring a jacket or sweater for when the evening cools off.
It is normal to feel "off" when at such a high altitude. Best way to handle it is to drink lots of water and electrolytes. Even when you think you have drank plenty, drink some more. Protect yourself from the sun. UV rays are extra strong and can dehydrate you quickly. Keep Ibuprofen on hand for the first few days.
Cocktail attire. We will be in our backyard so high heels are not recommended. It may get chilly as the sun goes down so bring a layer for the evening.
There will be a shuttle from the Gondola to the wedding Venue. Hotels / Rentals in Mountain Village and Telluride are walkable distance to the Gondola.