Make it clear and concise; include only the most important elements, keeping it at a maximum of half a page. To create the summary go back over your plan, pick three or four key messages and write a brief overview, then conclude with details of the action you want the reader to take.
That doesn’t mean you have to bust out Word and start the plan from scratch. A template is great--you probably aren’t doing anything that hasn’t been done before, so it provides a proven structure for your plan. Pretty much everything on it can be customized.
Set yourself a reminder to review your business plan regularly. If you have a team in your business, holding brainstorming sessions is a good way to benefit from their knowledge - it ensures you are all on the same page and that you get their support.
Business plans may target changes in perception and branding by the customer, client, taxpayer, or larger community. When the existing business is to assume a major change or when planning a new venture, a 3 to 5 year business plan is required, since investors will look for their investment return in that timeframe.