You've found your swimming pool contractor. You've determined a timetable, materials, and prices. Now it's time for your contractor to draw up the contract. Be warned, a contract doesn't have to look official--legally, anything you've signed can be used in court, so don't sign anything you're not sure about. Don't be shy about asking an attorney to go over the contract with you--this is a big deal.

Contract Basics
In addition to a scale drawing of the pool, the contract should cover: name, address, and license number of the contractor, dates when the work will begin and when it will be completed, a schedule of payments, and descriptions of work, materials, and prices. It should provide a Notice to Owner about state lien laws, a description of what a completed job entails, and notice that if that work isn't sufficiently undertaken within 20 days from start, it's a Contractor's License Law violation.

Contract Specifics
The contract needs to be very specific about the materials your swimming pool contractor will use, which means the quantity, quality, brand name, color, size, and weight of the materials need to be specified as applicable. The contractor should describe every detail of the project, including removal of debris and materials, and the cleanup. It's a good idea for you to give instruction regarding where the contractor can store materials while the job is in progress.

Project Description
The contract needs to describe the actual project and be as detailed as possible. Instead of: "set tile in green," you want your swimming pool contractor to write something like: "set green #777 ceramic five inch square tile, manufactured by Pool Tile Co., style #xyz to cover pool stairs, per plan." With a solid contractor and contract, you're on your way to owning a great swimming pool.
 
Source:
Hiring a Swimming Pool Contractor