How will you convince a customer to sell your products or services ?

you have to follow the below:

1- Ensure you know as much about your target audience as possible.

2- Decide which customers in particular you want to target.

3- Ensure you are clear about the unique selling proposition (USP) of your product or service.

4- Decide which sales methods to employ.

5- Consider how you will price your product or service.

6- Set yourself sales forecasts.

7-  Back up your sales efforts by marketing to potential customers.

First of all, you should have strong belief in your own product and use personally.