It should match your business: The name of your domain should possibly be your business name as well. This will make it easy for your potential clients to remember.
Generally people go by simple logic while searching the web and hardly anyone wants to memorize domain names altogether. Squatters have registered many common domain names and the best option for you, may not be available.
If you've just started or still waiting to start; then it will be worth the effort to first get the domain name and then name your business on that.
Successful marketing strategy involves synchronizing brand names with domain names. It should give a clear idea about your core business activity and not leave clients guessing.So you can get good business name ideas from a trusted company.
Keep it simple
Your domain name should be simple and easy to remember. This will allow you to generate more traffic as it allows people to use your website or email address to get immediate access to the service or information that you are providing.
You should keep the spelling very simple as well. If your domain name is difficult and awkward, it may be easy for you to remember, but you can't expect your potential clients to memorize it with ease.
Keep it short
As our main objective is to find a right name for our business domain, long names are tasking on the memory. Users are likely to make mistakes while typing it in.
Though your name must give a general idea about what you do, it should not go on explaining it. You should keep it as short as possible.