There are many flights routes to Bali that stop in Singapure on the way there. Specially cheap charters from Germany and the United Kingdom.
Just check out places like lastminute.com and edreams.com and trailfinders.com for the best flights available to Denpasar, Bali island of Indonesia.
Denpasar is the capital city of Bali and there is Ngurah Rai Airport.
