Why choose a short domain name !?
Simply because most people can’t remember long domain names. Try to register the shortest name you can, this way you will make it easier for your visitors to remember it and come back. You might want to register one word that has no meaning but easy to read or you might want to register 2-3 words related to your product name & business.

Domain names can only contain letters, numbers, and dashes. I recommend avoiding numbers and dashes.

The domain extension.
Dot .com is what most people try when looking for a website, thats why I highly recommend it. Your business might grow up and become well known over the internet. When it dose, you don’t want some domain hunter to grap yourname.net and yourname.biz Thats why I also recommend registering the .net and .biz of your domain.

Avoid free domain names.
This is about web hosting companies that offer free domain name if you buy a hosting package. Avoid this at all costs because they do register it but they are the legal owners of the domain name. You can use it as much as you want but your not the legal owner of it. This way they keep you stuck with them and they will take it from you if you try to switch to a better host.