Now you can either spray with water or use steam, or my prefered method… a hairdryer, yes the heat will block your work really quickly, and there is much less danger of “killing” acrylic yarns. Cotton yarns do need water or steam to block.
If you are going to use a normal steam iron make sure you DO NOT touch your work, as it will flatten it and can even “kill” some yarns, leaving them totally lifeless.
If you are blocking a finished piece, then you can wash it first and then block it. Sometimes having the piece damp helps to ease it into shape.
With more open work, like my “Bloomin Blanket” you have to get a bit more physical.
Here you can see the amount of stretch applied to bring the corners out to the required 16 inches. You may even need to weigh the sides of your blocking mats down to stop it curling up and maintain the stretch needed!