First, you will need to have a strong desire to be successful because all successful companies have a well planned and executed marketing plan. Many components comprise their marketing plans and they may vary depending upon whether you are a B2B company, B2C company, a manufacturer, a retailer, a service company, a reseller, a non_ profit or other specialty business.
When I ask entrepreneurs and small business owners, it is not unusual for not having any marketing plan. I once read that Sir Richard Branson never had any marketing plan when he started the 1st Virgin business many years ago. In fact in one study of entrepreneurship (I couldn't recall the name of the study) was that as much as 50% of entrepreneurs and business owners don't have a business plan and marketing plan when they first started the business.