Welcome!!!!!!! I live in CO also! Make sure the coop is bigger than you are planning on as chicken keeping is addictive! Provide one nest for every two hens you keep. Below are attachments that may help. Enjoy this website and we are here to help
Hello and Welcome To BYC! Mountain Peeps gave you some great links to get you started, be sure to check out the Coops section for lots of ideas! Good luck with your coop build! And you might want to check out your state thread for more of your neighbors and if they have any suggestions for dealing with the weather etc in your area https://www.backyardchickens.com/t/68894/colorado