Roll your pastry on a sheet of lightly floured baking parchment or greaseproof paper. Flip the pastry right over the tin, or filling, and peel the paper off. Patch up small tears by pinching or pressing, and fix larger gaps with trimmings. Try not to stretch pastry when lining a pie tin with the bottom crust, just ease it into the tin, gently tucking it into the edge of the tin.