Press. Also, If we call the upper 2 A, B and the lower C and D, Sew the A-B seam and the C-D seam. When you go to put the 2 pairs together, notice the seam allowances form the 2patches you just made. Pin the one on top so it reaches the needle first and the one (which you won't be able to see because it is against the feed dogs) should be moved so that the raw edges are towards you. This way, the seams are not pushed apart by the feed dogs and you don't have a huge lump unter your needle.
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