Get your domain name before someone else does.Quite often people will come up with domain names they feel are clever or cool only to find out that someone else had a similar thought and beat them to the registration of the domain name.
In some cases you may be able to register the .org, .net or other extension that may be useful to you, but in general most people are used to .com for commercial websites and .org or non-profit organizations. Register your domain names when you think of them rather than when you're all ready to launch a website.
Of course, this is fairly common knowledge and it is highly unlikely that anyone would invest the time to build a website around a domain name that they hadn't registered yet, but the faster you can register your domain name the better.
Most domain resellers offer similar services, however, take advantage of special or sales when they happen.
Basic tips for domain name format
Using dashes (-) in your domain name
Try to avoid registering domain names with dashes or using them as the main domain name. It is not friendly to users to have to remember to put dashes in domain names. It is also likely that they may end up at a competitors website. If the name you wanted to register is not available then use something else as your main domain name and use the version with dashes to create landing pages or forward to your main website.
Using capital letters in your domain name
Domain names are not cap sensitive, meaning that if you try and register SellFromTheWeb.com the capital letters will automatically be converted to lower case and the domain will show as being already registered. Likewise if you type in a domain name using capital letters it will automatically revert to lower case lettering and forward you to the correct website.
It is a good idea to use caps at the beginning of each new word in your domain name when printing and advertising it. It will be easier to read and understand.