Find a profitable niche. Starting with your interests, write down as many niche ideas as you can. Think about topics people might search online. Ideas include passions (like surfing or body building), fears (like spiders or speaking in front of crowds) and problems (like getting out of debt). Do keyword research to see it others are interested in the topic. Find out if a domain name is available that matches the keyword 100 percent. 
eBay is the most popular global auction site around and is a great place to sell items you no longer want. If you are looking to earn some extra cash, start out by looking around your house for things you no longer want; list them on eBay and watch as customers bid on them. You can also purchase clearance sale items and thrift store finds and make a couple dollars profit by listing them as well. The key to selling on eBay is to do your research and find out what the hot items are.