I don't work for ryanair, but my cabin crew uniform also creases badly when i sit down. Nothing you can do about that, especially if you have a long drive to work. Sometimes I wonder why I even both ironing it!! Also my shirt comes untucked all the time too. I've only got to open or close an overhead stowage and it comes out. They're not made for crew comfort I don't think. You'll just have to keep tucking it back in every time it comes out!!