If changes to your website include URL changes, it’s vital that the old URLs map to the new ones, this is because your site could fall out of the rankings as the search engines won’t be able to find your website.
Screaming Frog Crawl
This is something that would be best left to your tech team, but a screaming frog crawl allows you to check all your pages old and new so that you double check all content has been moved to your new site.
Updating XML Sitemaps
It is important that you update your XML sitemap so that Google can spider your site and see everything that is on the website. It is also important to update because if you have added or removed pages and have no updated the sitemap, Google will not be able to spider the site because there are pages missing, meaning that it will affect your ranking in the search engines.
Check all pages have been moved
Simple enough. Double check that all the pages from your previous site have been moved to the new design.
Checking any optimisation is moved over and updated
Make sure that all your H1 tags, meta descriptions, alt tags and url slugs are optimised and the same as your previous site because if you have optimised your previous site really well and it was ranking high in the search engines, you want your new design to be performing the same, so make sure you check.
Check the robots.txt so that you can see if Google and the other search engines are crawling and indexing your new site properly.
Search Console Informing Google
If domain name is changing (this is best avoided unless totally unnecessary) as well you can submit a change of domain through Google search console. You can also submit your XML sitemap through Google Search Console.
Monitoring Google and spidering pages after launch
You need to check your existing search rankings quite regularly to make sure they don’t drop rapidly and keep checking Google SERPS (search engine results page) to see how quickly the search engines are indexing your pages. If they’re really slow, then you know there is a problem.
Use screaming frog to do a thorough spider of your web pages to check for any errors like 404.
Ensuring GA tracking code is moved onto new site on launch
Making sure that your Google Analytics tracking code has been moved over to the new website is key, because if it hasn’t you won’t be able to track your leads/conversions meaning that you don’t know whether your lead is an organic user, has come through social media or a specific landing page.
Thorough quality control and checking all forms
Check check and check again. Make sure your enquiry forms are correct and that they are linked up to the correct email address because your potential leads could be filling out forms with them not being sent to you! So just have a clean sweep of the whole website and make sure if you were a customer, you would be happy visiting the site.