The main purpose of your application is to convince the Committee on Research Grants that supporting your proposal would be a good use of (their) funds. Your proposal will be read by panel members who are experienced professionals, but who are not necessarily experts in your particular field. Because they are evaluating proposals competing for limited funds, they must be critical and skeptical; only the best proposals will be funded.
Your number one job is to capture their interest. If you describe an important problem and then explain how you intend to solve it, you convert the reviewer from a skeptic into an advocate for funding your work. If, after reading your proposal, a panelist still asks "So what? Why is this important?", or, "What's the problem being addressed?", or "Can these objectives be achieved using these techniques?", then you have NOT been successful in your proposal. One good way to pre-judge how well you have gotten your points across is to re-read your application (before submitting it), putting yourself in the position of a reviewer. Or better yet, ask another person to read it from that perspective. When you look at your proposal from the point of view of the reader, you will see why it is so important to describe the problem you are addressing or the hypothesis that you plan to test. Without this firmly established, it is pointless to tell the panel all the things you will do in the field or lab. Don't stop there, however!
The logical next question is "Is that problem or hypothesis significant enough to be worth working on?" One way to assess this is to ask yourself, "Assuming I am successful in doing everything that I say I will, how many (of the relevant) scientists would want to hear the results?" If you conclude, "not many" then you need to rethink why you chose the project and explain its importance more convincingly. Don't feel that you singlehandedly need to solve the most pressing problem in Science - the scope of any project must be limited to what can be realistically accomplished - but do worry about how your results will contribute to the solution of a fundamental problem in your field, or why your field area is ideal for addressing a significant regional or topical problem. If your project is part of a large project, in the US or overseas, make sure that your part is clearly defined. Once you have established the significance of your project, outline what you will actually do - ie your research strategy. Make sure that you explain to the reviewers how these steps will lead you to answers to the questions you have set out to solve. This is the time to be specific: don't leave it to the panel to decide whether your research plan will answer the questions, tell them how it will! As for the budget, you should show the committee that you have carefully investigated possible expenses and have planned a realistic budget.
-Adapted from a Grant proposal writing guide created for the Committee on Research Grants at the Geological Society of America
Actually the above guidelines apply to most real life situations when we are begging others for favors or jobs.
1. State a problem.
2. Explain how or why it is important to solve this problem.
3. Show how you can solve the problem (and the benefit to your sponsor) if you get the favor or money to do so.