MySQL and Percona Server are binary compatible so the migration process should be like an ordinary MySQL upgrade process. Therefore the usual recommendation is to take a backup and then update it. Since you are going to migrate on production server is important to mention that the process has a downtime. It will be better if you first have the opportunity to test the migration process on a dev machine.
If you are migrating from different versions, for example from MySQL 5.1 to Percona Server 5.5 then you have to take some precautions.