A somewhat rumpled look comes along with linen. But I think the person who started this thread now has a linen suit that is beyond the rumpled look, particularily the slacks.
Use the linen setting on your iron. BUT, to get a really nice press, do this. Get a cotton teatowel, not terry cloth teatowel, cotton. Wet and wring out until almost dry, as much water as you can get out.
Now place that damp teatowel over the slacks and iron on top the teatowel. You will never run the danger of burning your linen clothing this way. If the heat gets too hot, the teatowel will scorch, not your clothing. You can spray the actual suit with a bit of starch before you iron if you wish, but it will not really help to keep the wrinkles out of linen for too long. Terry cloth will not harm your suit but it can leave fuzz on it and I highly doubt you want fuzz along with the wrinkles
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DO NOT, I repeat, DO NOT wash linen. It shrinks horribly.