So to make things simpler you can start process of proposal writing from defining guideline for content of the proposal. A proposal is generally written to force a reader to take an action, make a selection, to reach a decision, offer a job and many other such imperative tasks.
For personal proposal writing there written Request for Proposals (RPF) is not required. You just need to guess about a service required by reader to take action and prepare Proposal according to that guideline. It should be better than a resume and a work plan.It should be like an introduction, to an extent statement of qualifications, a work plan, pricing, and articulation of the reasons and approval of recommendations.
Your proposal should be an extension to believe that you will go to achieve for your client. The time it will cover while accomplishing the task, required resources, benefit from the project, costing, Staffing, Management and Oversight, Allocation of effort, Orientation and Phase-In, Deliverables, Metrics, measurements, performance standards and quality assurance all should have mention in your document to make it a successful business proposal.