So, although a detailed business plan may not be required for an online business, I am going to include it here so you can at least look at and consider each section and determine yourself if it applies to your business.
Marketing Analysis/Strategy: The next thing to write (after the general description) should be your marketing strategy. For new or existing businesses, market analysis is an important basis for the marketing plan and will help justify the sales forecast. Existing businesses will rely heavily on past performance as an indicator of the future. New businesses have a greater challenge _ they will rely more on market research using libraries, trade associations, government statistics, surveys, competitor observations, etc. In all cases, make sure your market analysis is relevant to establishing the viability of your new business and the reasonableness of the sales forecast.
A recession is the optimal time to reinvent competitive advantage because the pressure of a feeble economy will separate the strong businesses from the weak ones, with the weak falling out of the game entirely. Your business will be strong if you have a plan of action based upon a little industry research, an analysis of what you have and what you want, and continuous monitoring of the results of your plan. This kind of innovation is not only a necessity right now, but it is an opportunity to improve the quality and efficiency in the way you do business.
Financial Plan _ The financial plan consists of four sections: Financial Worksheets, Cash Flow Projections, Financial Statements, and Additional Financial Information. All of these components will tell the story of how you plan to start or grow your business from a financial perspective. It is vital that you explain the assumptions under which you have based your projections, for example, "We assume that there are no unforeseen changes in economic policy to make our products and service immediately obsolete." or "We assume interest rates will stay the same over the next three years." (both quotes from Bplans.com sample business plans)