Easy answer is to use an ironing service to be honest but if you want to do them yourself then I can only say how I do mine:) First of all decide if the want a razor sharp crease down the leg - for jeans, chinos they're a bit unnecessary in my opinion. I do casual trousers this way - with zip open slide the left hand top of garment over your board, iron then move to right hand side, left back, right back , then do legs flat both front and back. If you want creases then do the top bits the same way but when you do the legs fold the trousers the same way as you see them hanging in a shop and press so you get an edge down the front of the leg. I take suit trousers to the cleaners - they do a much better job:) and no, I don't run a postal ironing service lol