Press any wrinkles in the PLEATS before removing the basting stitches which are just holding the pleats in position for transport. Make sure the thing fits right around your waist and hips before removing the basting, however, as if it does not fit you will want to leave the basting in when you send it back for a refitting. If the only wrinkles are in the Aprons you can usually iron those out with a good steam iron by flipping the kilt inside out and placing a bath towel on top of the kilt, which should be on top of your ironing surface. Iron the aprons smooth throught the towel with lots of steam, then hang that baby up to let it set up as the steam cools and dries. Repeat as needed. If you need to iron the aprons leaving the basting stitches in helps to make the rest of teh kilt a lot less unwieldy, so iron whatever you have to, make sure it fits and looks good, then remove the basting.

Enjoy. B&S make a nice casual kilt. I have one in Weathered MacDonald.