Bra straps that are too short can press into your shoulders and cause red marks and discomfort. Short bra straps can also cause the underwire in your bra to dig uncomfortably into your rib cage. Contrary to popular belief, bra straps are only meant to be stabilizers and most of the weight of your breasts should be supported by the wide band of your bra. Most bras come with adjustable straps, but if you find your bra straps still aren't long enough on the lowest setting, there are some other things you can do to lengthen them if you are handy with a needle and thread.

Locate the adjustment slider on each bra strap. The adjustment sliders can be made of metal or plastic, and are typically found on the back of each strap. It's easier to lengthen the straps this way with the bra off.

Grasp the adjustment slider on the left edge and the right edge with your thumb and index finger. Move the slider down toward the back of the bra. Some bras have the reverse arrangement, in which case you move the slider up toward the shoulder to lengthen the strap.

Experiment with different lengths. It will take some trial and error to find the proper bra strap length. If you have the strap lengthened as far as it can go and it is still too short, you can add more length by sewing in a strap extender.

Move the adjustment slider so the bra strap is the longest it can be. Typically, the slider sits close to the shoulder in this position.

Cut the strap from the bra at the point where the bra strap meets the bra band.

Determine how much length you need to add to the straps to ensure your bra fits comfortably. Place the bra band where it fits around your ribcage properly and have a friend measure the distance from where the original bra strap ends to where it now needs to attach to the bra band.

Cut two pieces of strap elastic to 1 inch longer than the length you just measured. Use strap elastic that is the same width as the bra strap you are extending.

Overlap the end of the original bra strap slightly with the one end of the strap elastic you measured and sew the two pieces together securely using a needle and thread.

Secure the free end of the strap elastic to the same spot on the bra band where the original strap was attached with a needle and thread. You can still adjust the bra straps if necessary because the adjustment slider is still intact.