1. An executive summary outlining goals and objectives.

2. A brief account of how the company began.

3. Your company's goals.

4. Biographies of the management team.

5. The service or product you plan to offer.

6. The market potential for your service or product.

7. A marketing strategy.

8. A three- to five-year financial projection.

9. An exit strategy.

See these steps in detail here.
 

Other resources for Business Plans:

SBA; US Small Business Administration (a Video Course)

Free Sample Business Plans

How to Write a Business Plan (AmEx Forum)

How & Why Writing a Business Plan Makes a Difference (AmEx Forum)

Business Plan Tutorial

How to Write a Great Business Plan (Inc.com)

A Better Business Plan Can Lead to New Customers (Entrepreneur.com)

Why Business Plans Don't Deliver (Wallstreet Journal)
The five most common flaws and how to fix them

Writing a Business Plan (Digital Women)

How to Write a Winning Business Plan (Forbes.com)

How to Write a Business Plan (themoneyalert.com)