Marketing and sales start with product or service design. If you design something people really want, it’s a hell of a lot easier to market and sell.
Is what you have to sell what they want to buy?
Why do you sell what you sell?
Are you trying to sell something you came up with or had or learned somewhere, or did you start by asking what problem people had that they wanted solved?
Is what you have what YOU want to sell, or what CUSTOMERS want to buy?
I have a product that I believe will help people. I have done a lot of research, dozens of prototypes, focus groups with a few nice endorsements. I think I got it right.