How can I extend my tourist visa in Thailand for a few days before flying to Bali?

The user is seeking advice on how to extend their tourist visa for a few extra days in Thailand before traveling to Bali. They mention their current visa extension ends on May 14 but want to stay until May 20. Commenters suggest visiting the Immigration Office to apply for a new Extension of Stay, bringing flight tickets as proof. They recommend not applying too early, as a rejected extension will give a 7-day grace period from the application date.