From Creative Market:

The perfectly prepared and written design proposal is the difference between getting new clients and watching opportunity after opportunity leave you behind. Unless you’re working as a full-time designer at an agency or company, you’re likely in business for yourself as a freelancer — which means that you’ll have to write a number of proposals over your career to constantly get new clients.

Learning how to perfect this art form means more clients, business, revenue, and successful projects in your portfolio. In time, you should become so adept at prepping proposals that it’ll be almost like second nature to you — as seamless as choosing the right color palette for a project or invoicing your client for a job well done.

Click here for the full article: How to Write a Design Proposal: The Ultimate Guide