Cut the lemon/lime in half. Then cut the far end of the fruit off too. Don’t take too much flesh off, just the rind at the end to open it up.

Put the fruit half in your juicer with the halfway middle cut facing down and the end of the lemon/lime facing up - it’s hard to describe but you can see below 🙈 I think most people put the half in the opposite way round to match the shape of the lemon juicer.