Those of us who learned to sew by following pattern instructions find we have some gaps in our knowledge down the road. A case in point: pressing seams open.
The Big Four pattern companies sometimes mention this crucial step in construction in the glossary section of the instructions, but more often, it's just the last, short sentence in a sequence of steps. "Stitch side seam. Press seam open." If you're lucky, they've provided an illustration of the wrong side of the garment and the tip of an iron is magically parting the two little seam allowances open and pressing them flat. So for years, that's what I did — I just turned my garment wrong side up on the ironing board, slid the tip of my iron into the seam allowances and ironed away.
But I've learned a couple of other important things about pressing seams since then. The first is, press that newly-stitched seam with the raw edges still meeting and "meld" the stitches into the fabric. Let it cool briefly. Then, press the seam open. The difference may be subtle, but I've found it really helps keep your work neater and more "professional-looking."
All right, that's simple enough. But what about when you're dealing with seams that are hard to get to, as in this baby blanket I'm making? Essentially, it's like a big pillow case. I've sewn all four seams (leaving an opening into which I stick my hand and turn it right side out, of course). I can't really pull it over my ironing board for pressing the seams open. The solution? Press one of the seam allowances like so:
And then turn the work over and press the other one:
When you turn your blanket (or pillow case) right side out, you'll have a much crisper and sharper seam.
This technique is also really useful on curved seams, such as round collars or circular pillow covers.