Bali is serviced by the Ngurah Rai International Airport, which is also known as Denpasar International Airport. Bali is well-connected to the rest of the country by a robust network of flights and internal transports. From India, one can take the Thai Airways, AirAsia X, AirAsia or Cathay Pacific as these are the most common flights operating to Bali. Flying from Chennai or from Cochin often works out to be more economical.
Travelling by any other means to Bali is neither economical nor convenient. Thus, flying works out to be the best option.