This guide is pretty good but misses a couple of steps!
https://www.quicksprout.com/2015/09/16/the-simple-guide-to-moving-your-wordpress-site-to-a-new-domain/

1. Download the contents of your current public html folder
2. Open phpMyAdmin
3. Export the database to a file on your local machine
4. Import the database to the new site
5. On the new site, update “wp_options” table so that “home” and “siteurl” points to the new domain
6. Edit the downloaded “wp-config.php” file so that the following are correct for the new domain:
   • DB_NAME
   • DB_USER
   • DB_PASSWORD
   • DB_HOST
7. Upload the amended files to the new domain