Make it easy to remember. This is why many businesses get domains with their business names in them. Some people even choose their business name after they have a domain they like.
Shorter is usually better because they’re easier for customers to remember. It’s also easier to get matching usernames for Facebook, Twitter and any other social media accounts you have.
Get more than one. As traffic to your website increases, you may attract the attention of copycats who’ll snatch up similar domain names in the hopes of drawing traffic away from you. Register similar or misspelled domains early so this won’t be an issue later.