Eva, ask away! I can't find the link to the web site with the tutorial (maybe one of our members could give it again), but my blocks were slightly small - 1/8th to 1/4", so I misted them with water (its best to use spray starch but mine already had plenty of starch in them). I drew the exact size on cardboard and simply stretched the block to fit starting at the corner then the middle of the sides, etc. When it dries it holds its shape to the proper size.
Thanks for asking!