Make sure that you are pressing and not ironing. Ironing may stretch the material and make it look uneven. Here's a trick: tape it to something (like a plastic piece) or pin it down really well to the floor (carpet). Take a spray bottle of water to it and get it damp. Then let is dry. This may help to straighten it out some. Also, it helps to have something with good right angles to lay it on to see how it looks in terms of straightness. Make sense?