When painting casement windows, make sure they are wide open. Paint the top, side, and bottom edges first, then finish with the crossbars, frames, casings, and sills. 1. For double-hung windows move each sash to the center of its track, and paint the inside sash, starting with the crossbars. Then, paint the frame. Don’t paint the top edge of the inside sash; you’ll use it to move the sash. Next, paint the top half of the outside sash, starting with the crossbar, then the frame. 2. Close the sashes to within several inches of the closed position. Paint the rest of the outer sash and the top edge of the inner sash. Paint the window casing, then the sill. 3. Paint the check rails. Move both sashes down as far as they will go, then paint the upper rails. Once the paint is thoroughly dry, move both sashes up and paint the lower rails of the window.