Just as easy to walk Vic to Picc (or v/v) than get the bus, Jimmi. Picc you come out the main entrance, down the ramp where all the buses and taxis come up. Follow that road until you get to Piccadilly Gardens. Keep walking alongside the east end of shops etc on Piccadilly Gardens and follow the tramway all the way to Manchester Victoria.
20-25 mins it takes. Easy!