• What your specific niche/topic for your online business.
• What the keyword you want to use.
• What product you want to offer.
• Prepare some alternative of the name of your business.

Make sure you consult with other people. Tell them you are starting an online business, and get feedback from others. Every opinion from other people especially experienced domainers are valuable to consider.

Before you register a domain name, here are some other things you need to know:

Choose dot com. Dot com name shows that you are serious with the business.
Choose the name that represents confidence, reliability, strength and trustworthiness.
Choose short domain name as possible.
Avoid choosing numbers in your domain name because it might be confusing.
Include one or two keywords in your domain name, and use broad keywords that cover a lot of territory so you can expand your business into new direction that you may not be aware right now.
Check your keyword popularity before you make a final decision. Using WordTracker or Overture will help you to find the good keywords. Use the keywords with the most searches.

Dedicated to Anne Ahira and the community.