If you are someone who shies away from planning, or you don't like writing or preparing documents, nevertheless you are going to have to force yourself on this occasion. I say that because it is such a key document for the future success of your business, such a tool throughout its development to return and refer to.
Preparing a Business Plan: A business plan has to be in accordance with the organization in question, its situation and time. However, a business plan is not just a document to be produced and filed. Instead, business planning is a continuous process. The business plan has to be a living document, constantly in use of monitor, control and guide the progress of a business.
It seems to have been put there to fill the need to attribute a certain sum to marketing. Make sure you are researching each point of your budget, make sure that you are giving it context and it makes proper sense within your overall plan.
When I have received business plans, the very best responses come from people who have looked at the risks and have an answer for every question. What you never want is to throw a scenario at your plan and have to answer "I don't know what I would do in that situation". You want to plan for every possible contingency, and certainly all the major risks to the ongoing success of your business.