Flat Seam

Lay your two edges, whether straight or slanting, exactly even, tack them together with stitches 2 c/m. long, distant 1 to 2 c/m. from the edge, and then back-stitch them by machine or by hand, following the tacking-thread. Cut off half the inner edge, turn the outer one in, as for a hem and sew it down with hemming-stitches.

Smooth the seam underneath with the forefinger as you go, to make it lie quite flat. Beginners should flatten down the seam with their thimbles, or with the handle of the scissors, before they begin to hem, as the outer and wider edge is very apt to get pushed up and bulge over, in the sewing, which hides the stitches.