Start by laying fabric with right sides together. Straight stitch 1/4 inch from edge of fabric. Backstitch at begining and end.
Press seam open
I present: Plain Seam
The Book says: "The most comon seam and is used to sew two pieces of fabric together. The length of the stitch is between 10 and 12 stitches per inch. The width of the seam is usually 5/8 inch for fashion sewing and usually 1/2 inch for industry sewing."