Borrow it form family, friends or from the company in which you are working for. Else use credit card and then pay some higher interest . Do some part time job for few months so that you can have extra money and pay it.
I think it depends on the need and the desperation. I mean like if you need to buy a bike, you are surely not gonna ask the boss for a early payment, in that case family can help. And in case you need something very badly, then you should ask for your higher authorities.