Your sales should go into detail about how the sales transaction will actually take place. What steps do your sales reps go through to actually close the sale. What is their commission structure? What are their incentives to sell? How much are they involved in the actual delivery of the product or service? What is their role after the sale? Are they divided into territories based on geographic regions, product lines, or something else? What is the organization of your sales department and how will that specific way of organizing and compensating put you ahead of your competition?
When it comes down to it your sales forecasts may be only slightly more scientific than throwing darts at numbers on the wall. Use your instincts, what you know about your market, the experience of your sales team, and the strength of your marketing program to come up with an educated guess for your sales forecasts. If you have set sales goal for your sales team already then it may make sense to base your projections on the percentage of that goal that you feel will be achieved by each rep. Estimate sales figures for each rep on a monthly basis and you should have a good starting point for your projections.
Do you see opportunities for strategic alliances with non-competing companies? These types of strategies can be very beneficial for startups. Make sure your agreement is well thought-out and your company is not getting the short end of the stick.