BuddyPress.org

Backup database of whole installation and backup server WP/BP files and folders – don’t forget to get backup of .htaccess and wp-config.php file in root as well.
If you’re keeping same domain name and just pointing it to new webhost, it’s a simple process.
If you’re changing domain name and getting new webhost. You’d need to do a search and replace of site URL in backup SQL file and import to new database.