It's not really advisable to improvise when coming up with business strategies. It's better to stick to time-proven sales methods that have always worked and that are used today. The three main ways of increasing sales volumes and increasing the average value of orders are “upselling”, “cross-selling” and “next selling”. These three general principles are used in all possible business sectors, from selling bank services to the largest corporations to working in a fast food restaurant. And you should definitely know them as well.