Bologna is served by the Guglielmo Marconi (Bologna) International Airport, very close to the city. And due to it's gepgraphical location, it's common to reach Bologna by rail.
Flights from India to Italy are available from nearly all the international airports of the country. Airlines such as Qatar, Etihad, Air India, Jet Airways and many other airlines provide flights to Rome. Air India operates direct flights only from New Delhi and Bombay. From Rome, you can take another shorter flight to Bologna, or take a train. Turkish airlines and Aeroflot have direct flights to Bologna from Delhi and Mumbai via Moscow and Istanbul respectively.
Bologna is well connected by air to both important cities in Italy as well as all over the world. Some of the common routes were via Roma, Istanbul, Moscow etc. Alitalia has cheap flights to Bologna from Rome.
You can also rent a car from the main cities, but parking in Bologna can be very difficult to find. Renting a taxi is relatively easy, and roads to Bologna are good.
Due to it's central location, Bologna is connected to all main cities in Italy such as Rome, Florence, Venice, Milan.
There are several buses that depart from the capital city Rome to Bologna from Roma Tiburtina or V.Salaria,665.
Bike is the most famous and convenient form of transport and most tourists rent a bike - with many places in Bologna renting out bikes. Walking is also much recommended, as there are easy to undertsand road signs everywhere in Bologna. All you have to get is a map from the tourist information centre and orient yourself to major landmarks.