I'm changing my site domain to something shorter. Any tips on best practices so as not to lose rankings? What happens if I keep both sites for awhile? I assume I wouldn't be able to move my content over, as it would create duplicate content errors. How do I keep my ranking? Thanks for any advice!
get the new domain and park it on your hosting account, then point the new domain to the same location as the old. You can begin marketing the new one without losing any rankings, clients etc that use the old one. it's just two different ways to access the same site.
People do it all the time with their sites. You just need to work on the ranking again and start over almost.