1. Be sure that you're entering your payment details on a good site. Try to find "https://" inside the URL in the site that you're seeking to buy something from. If you don't see that or no indication of any website security, then it's probably a wise idea not to trust those people with your account information.
2. When you are online shopping, you should only shop at reputable stores. If the store does not have a good reputation, you may be seeking trouble. Many people have had their credit card and private information stolen from shopping on less than reputable websites. Be careful and protect your private information.
3. Be careful which sites you patronize. It is difficult to know which are in the up and up and which are not, but there are a few clues. If the address does not seem sensible or the design seems off, go to a different site. Furthermore, if a lot of pop-up windows begin appearing, close them out and move on.
4. If you're considering buying a product online, look into the reviews. The reviews using their company people that have used the product can give you a great idea about the product. You may be able to find out the standard of the product, when it worked as described, and if you should have the purchase.
5. A great tip to keep in mind when you're thinking about online shopping is to make sure the site is legit. You don't desire to be giving your credit card information away to somebody who could potentially scam you. Always look at the site to tell if it's professional and safe to use.