By the way...! You can sew the edges of a tablecloth using the same technique - just with slightly wider turnings.
1.Press seams 2 cm to the wrong side all the way around. 
2.Mitre the corners, as shown in the photo. 
3.Press the seams 1 cm to the wrong side. Press the corner into place, as shown in the photo. 
4.Fold, press the seam 1 cm to the wrong side again and sew all the way around.
