Just curious but is it thin paper like a print or thick with a bit of texture like a watercolor paper ?? Regular print stock would likely fall apart if wet like that !! Problem is the water weighs it down and when you try to lift it,,it tears !! If its thin paper like most prints,, lay it on a piece of window screen to wash it,, dont try to pick it up !! When done take an edge and gently slide it onto a sheet of glass to let it dry !! If it curls and it likely will,, cover with a thin cotton cloth and press with a warm iron on a table or some flat surface !! Watercolor paper is made to be wet and re-wet so not a problem with it but if you dont have a stretcher to put it on so it will dry flat just hang it with clothes pins,, you can also iron it after its dry !!