If you are thinking that your pulsar is not performing as it performed when it was new, then you should better check your spark plugs. The spark plugs are very important parts of petrol engines. Spark plugs can be cleaned with alcohol or kerone. For rubbing out the carbon deposit you can use sand paper. If your spark plug look as shown in the picture, then it definately needs cleaning.
To take out the spark plug you need 16mm tube spanner. You may have to take out the fuel tank a bit to unscrew the left plug.
For Pulsar's the spark plug needs to be cleaned in every 2500km. The manual says to replace both plugs at every 10000km.
Pulsar has Champion plugs as stock.
You can even opt for NGK Iridium plugs if your wallet is happy.