How do you construct a Financial Plan Narrative?

I believe you are referring to writing the Financial Plan section that is part of the overall Business Plan needed to start a business.

The Financial Section provides a forecast, or an "educated guess", of anticipated sales and expenses reported at different times if the business were to open. In writing this part of the business plan, it is important that the following components are defined:

• Sales forecast that outlines the projected total sales and "cost of goods sold" during the first month, first quarter, and first year.
• An expense budget is needed to project fixed costs (labor and rent) and variable costs (marketing expenses) during the same time frames as above.
• Develop a cash-flow statement showing the movement of money into and out of the business through revenues and investor proceeds and expense payments. This is not the same as an Income Statement.
• Income statement is different from the cash-flow statement in which it summarizes revenues minus expenses cumulatively to determine projected profitability, monthly, quarterly, and yearly.
• Projected balance sheet showing acquired assets and liabilities.
• Break-even analysis is probably the most important part of your narrative because any lending institution or business investor will want to see the projected point the business will be profitable.