A business plan should be detailed. In listing your products and services for example, you should not really stop by just enumerating them. You also should write down the descriptions and scope of your products and services, touch base on production and identify means on how you can market your "brain - child" to your targeted niche.
Once you have done all this you should have a complete and detailed professional business plan. The most important thing to remember when developing the plan is to see it as a living document and include specifics regarding dates and specific responsibilities. Your plan will need constant reviews and updates and things change so expect it to be a work in process for a good stretch of time. It will all be worth it in the end, a well-written plan will help ensure that the business is fully focused on what is required to achieve the company's goal.
A brief account of how the company began- You should mention in your business plan the history behind the formation of you company and the background of the founders and directors.
Products or Services Offered : Here you will give a summary or the products or services you will be offering. For example if you were producing hand crafted wooden jewellery boxes you might describe the wood that is being used in the construction as well as the techniques that you use to produce these boxes.