It’s easiest to iron your piece when it is still damp.
Place your cross stitched piece face-down on your ironing board.
Use the steam function of your iron, and ensure your iron is clean before you preceed. If you do not have a steam function on your iron you can lay a clean wet kitchen towel on top of cross stitched piece.
With a warm iron, press the work from the back. Make sure to keep the iron moving at all times so you don’t damage the fabric.
Always iron from the backside of your embroidered work. You may damage or flatten your stitches when ironing from the front.