Fraudulent buyers are often in a hurry. The more a customer asks you to hurry/rush the more suspicious you should be, our real customers always have patience.
Fraudulent buyers often suggest doing all or a part of the transaction outside the escrow and then do not complete their part of the transaction.
Be careful about photoshopped payment evidence, don't release Bitcoin until you have confirmed that you have received the money. You are not obliged to release a trade until you can verify that you have received the buyer's payment.
Don't open any links that your trading partner is sending to you. If you must, use different browser than the one you are usually using.
Don't visit websites other than CoinCola with the same browser that you're using to trade. Use a different browser to navigate on other websites.
Bookmark CoinCola in your browser and always use the bookmark when visiting the website. This helps you to avoid accidentally visiting phishing websites, they exist and can be very convincing. Even experienced traders have fallen victim to phishing websites.
If you're unsure about a user, you can always contact support for help.