Pressing (ironing) a suit is a hell of a lot more difficult than touching up wrinkles with light steam while avoiding seams. The potential for spectacular failure when taking a hot iron to a suit is high - so I would NEVER recommend to anyone to iron their suit. Of course, we have experienced professionals in this thread for whom manipulating steam, ironing cloth and heavy iron is part of their everyday life but for mere mortals, it could quickly result in shiny wool and messing up all the good work that the tailors have put into shaping your suit in the first place.
guide to touching up your suit without wrecking it - Page 12
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Yup, that's why I mentioned "touching up". I've never had the guts to press my jacket lapels, chest or shoulders, and that even though my garments are either RTW or MTM and have almost no iron shaping work.
But for touching up, my experience has been far worse disasters with just steam than with the iron. Puckered seams all over the place. Not to mention steam removes trouser creases. You can't just steam your trousers, you'll have to press them sooner or later.
Steam does ruin iron work, too. So the best thing you can do is get some directions, maybe from your tailor, and from this thread, and use the iron for touching up. Of course, you shouldn't press a whole suit all by yourself.
However, if I had nice bespoke garments, I think I would not use steam nor the iron myself
Edited by RDiaz - 11/5/13 at 3:40pm