Network Design Efforts and documentation

I would like to know if there exist a simple guideline that I can use to document the scope and process of installing a new network? I have just engaged in my first large project of installing a new server centric network that has to be tightly integrated with a phone system. This project is for a hotel that requires voicemail and internet access to every room. What’s in place now will not work. A new system must be installed in a timely manner to avoid having a large hotel with no phones and no information management system other than stone and chisel. System will eventually include electronic card-key door locks and a website for remote room reservation easing the ability for guest to reserve rooms and check in.