The thread found at the link above is your one stop place to go to find out how to maintain your Nike SBs. Below is a guide on how to uncrease your SBs!
First of all a tip: Clean the dirt from the ridges of the creases with a wet towel and some soap. Clean the toe box, it makes a big difference because the dirt makes the ridges in the toe box more visible.
Step 1: We start off with a creased SB, in this case my first SB ever.
Step 2: After cleaning shoe, place plastic bags inside toe box to fill it. Then wet the toe box and place a rag ( I used a T-shirt ) on top of the toe box. Make sure the toe box is moist at all times! ( During this process )
Step 3: Place iron on top of toe box and iron, applying pressure on top of the toe box to remove creases.
In the end..
Comparison: One being ironed and the other not having any work done on it.