Prepare a customer profile for your product or service. Most companies report that about 20 percent of their customers account for nearly 80 percent of sales volume. In forecasting sales, your first step should be to identify the customer group within your target market that accounts for the majority of sales. Your customer profile will largely depend on what business your company is in. Examples of customer profiles are: middle-aged professional males who like to golf, low-income households in a particular area and small business owners who are looking to expand.