Do not try to write your business plan in one sitting. As I mentioned in the beginning, for a traditional brick and mortar business, it could take in excess of 100 hours to compile all of the information needed into a comprehensive but yet understandable document. For online businesses, probably not that long. But your final product should be well thought out, well documented and easily understandable.
Start by writing a description of your business, including what stage of development it is currently in (conception, start_up, first year, mature, exit) and your plans for growth. Discuss the nature of your business, the main products and services you offer, the market for your products and services, and how and by whom the business is operated.
If an online business, you need to go into detail how you will attract customers to your website. General statements like "I will use Face Book ads and email marketing" will contribute almost nothing to helping your cause unless you have detailed statistical analysis of tests you have conducted or of another similar business you have been associated with. If you do not have any data upon which you reference your estimates, it could show lack of proper thought to the remainder of your business plan.
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.