HI what type of stained glass?
If you don't know then use johnsons baby shampoo and warm water and cotton wool in a circular motion renewing the wool as needed. But check the quality and if possible what the colour fixative is. A ginger pubescent boys urine was the urine of choice when they did Canterbury.
hi, for use with any glass.....newspaper!! i was told for years this was best and never got good results.......until recently...the trick is........use wet newspaper to wash glass and then use dry newspaper to buff up...........amazing.