Make sure you keep your arm hanging down at your side, fully extended. If the handgrip is not level with the crease of your wrist you will need to adjust it.
To adjust the height you simply have to push in this button and shorten or lengthen the leg extension by pushing it up or pulling it down. If it doesn’t move, the spring button is probably not completely pushed in.
You can look in a mirror or ask someone to judge the angle for you if you can’t see it. Be sure you check that both crutches are the same height.
After checking this, tighten the ring you can find below all the adjustment holes. This ring is called the collar, and you can tighten it like you would a screw or a jar lid.
Or, more precisely, one or two inches below the bend in your elbow. They should not restrict your ability to bend your elbow.
Push the button in and shift the cuffs up or down according to your requirements. You will see that the cuffs move up and down a series of adjustment holes that are visible along the side of your crutch. If your cuff is more of a horseshoe shape and has an opening, the opening should be facing forward, the way you are facing.
Sometimes with forearm crutches you can widen or narrow the width of the cuffs so you get a good fit around your arm. You want to be able to move freely, but with a secure fit.