Make a new thread with all the usual details ( domain name, maybe a short description, registrar, payment options, expiration date, auction deadline, ... it depends on what type you choose : auction, fixed price, make an offer).
First you have to buy a domain name. That is a golden rule for selling a domain name. You just have to buy one. You cannot short sell it like in stock market.
Luckily for you. I can guide you with that. On how to buy it. Selling we will tackle later when we have some free time.
I have some for sale at just 200,000 USD each.
Great returns, in short period of time. Lets pillage those retirement bonds and savings of your parents/relatives/friends/family.