A good domain name is no longer than two to three words. Having a short domain name makes it easier for people to remember. You can include keywords in it such as what you sell or the location you're based in. You should not include many symbols or numbers, as it makes it harder for people to type.
Domain names are purchased, generally with a year subscription that can be extended. This usually costs $10-$15 a year.
My business would sell Christmas trees and would be called Cloud Nine Pines. The domain name would be "cloudninepines.com".
This would be a good domain name because it is relatively short, has the name of the business in it, and is easy to remember. According to name.com, this domain is available.
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