As companies evolve, they may find their domain name is obsolete now. It is very tempting to change the domain name, but if it is an aged domain with good rank, can you keep your good ranking in Google? A permanent redirect will allow you to keep you your authority, however it can be complicated if you are not tech savvy.
When you use server-side 301 permanent redirects, Google will transfer your domain's rank, as well as directing visitors to your new website. This is what Google recommends; they offer videos to help you through the task. It's possible to DIY, however, one mistake could affect your ranking and, if your company's sales depend on consistent Internet traffic, taking a few days to correct any mistakes may cost more than it would to have a professional handle the 301 permanent redirects. If you are comfortable via inserting new code by way of your .htaccess file (Apache), you should be fine.
Do not make any major changes to your site until you are certain that the redirect is working for every page, which will take a few days. If you start a complete rebrand and something goes wrong, you will have a tough time isolating the problem.
Don't be in a hurry to change your domain name; it is not a decision to take lightly. You will have to change your stationary, such as business cards and invoices. Additionally, you will have to change any digital and print ads where you mention your website address. While Google will redirect visitors, people are wary of typing in a domain or clicking on a link and then they land on a website with a different domain.
If you do change your domain, try to find one that is evergreen and will work for your company no matter how many times you rebrand.