As I have starched all my fabrics before I cut into them, most of the bleeding and/or shrinking is hopefully done. Before I put the blocks together in a row, I'll press them using a mist of water as my steam part of my iron has died. I can't seem to keep an iron's steam working for more than a year. So instead of buying yet another iron I just keep a water bottle handy. Gives me a nice crisp block with all their seams pressed flat.