How to sell
Take a job in the company where you teach. There are different methods of sales, which should be used in different situations. Some companies prefer to recruit new employees and train them to sell their goods from scratch. Try to get a job in a similar company. Successful experience will help you in the future to switch to selling more profitable goods and master other methods. The main thing is to start.
Read about sales and apply in practice. There is a good book "The Lucky Merchant" written by Frank Bettger. It outlines his personal sales history. He shares, as in the beginning everything did not work, and how he became the best seller of the company. Look for other books. Read and note as much as possible. And do not believe anyone for a word, check everything in practice.
Go through the trainings "on the side". Do not stop at what you are taught in the company. You're not going to work here all your life? There are many more profitable products for sale - cars, real estate. To go to this level, you have a lot to work on yourself. Go to all the trainings that you can afford. Better save on entertainment, then all this will pay off.
Try, try, try. The more experience, the easier it is to apply something new.