One of the best ways to increase net profit is by growing revenue, so long as your gross margin is healthy and improving.

And there are three areas that drive top-line revenue growth.
Leads generated, sales converted, and revenue per customer.
So along with the Unique Selling Proposition and Guarantee and the Sales Management System, the Tactical Marketing Plan is one of the main strategies we use to achieve revenue growth.
The tactical marketing plan is the tool we use to plan, measure and manage our efforts and achievements of these three things.
A tactical marketing plan does not need to be complicated. Pick the few actions that will bring in leads, decide how you will measure them, and review the numbers every week. Small, steady improvements in each of the three areas add up to real revenue growth. To see how this fits with selling, have a read of how to improve sales conversion rates. For general background, there is a useful page on marketing plans on Wikipedia.