You can look online for sample proposals that you can work from, in many cases you will be able to download a template that you can work from. You will most likely find that there are dozens of sites offering hundreds of different templates to download. It may take a while, but you will find that there proposal forms that will match almost any need including yours. Take your time and select the one that best suits your needs.
Templates are a major time_saver: The most obvious benefit of using a template is that it's a major time_saver. You don't have to create everything from scratch because a lot of the complex work is done fore you. A template allows you to drop in the look you want and then customise according to your needs. This is significantly faster than starting from a blank canvas. Templates can give you a competitive advantage: When you manage projects and delivery it successfully, it's essentially competing with other project managers, departments or against another company.