Young Brunette Girl Posing On The Bed With A White Fitted Sheet

Usually a flat bed sheet is overlocked around the edges to form four seams. One of the seams is wider than the other three and helps with orienting the sheet correctly on the mattress. The wider seam goes at the head end of the mattress. Sometimes the sides do not have seams, but are finished with the selvedge only.
When one makes a bed, the patterned or monogrammed side of the top sheet is placed facing down and then the top edge is folded towards the foot of the bed, exposing the design.