The usual hesitation to do jeans alteration is due to the thichness of jeans material. The key is to use heavy duty needles and thicker threads especially made for jeans.

To shorten jeans, take one of your favorite jeans with the right length and measure the inseams from crotch down to the jeans’ bottom. Take this measurement and add a few inches for the hems. If the hem is ½ inch after stitching, then add an extra inch before cutting the jeans. Use ½ inch as first fold and another ½ inch for the 2nd fold.Stitch in place.