I found out the hard way that when I was finger pressing my seams open, I was actually distorting the shape of my nails (I have claws). So I bought a finger presser from Clover, it's a roller that you run back and forth on your seam to press it open. I also have a Clover mini-iron, so after the finger press, I run my mini-iron over the seam to set it, then I press the whole block with my iron and wool mat. I also use Sta-Flo starch, very weak solution of it and then I leave it alone until it cools.