How do I snip the brown leaves from my fern? I have a fern, and it doesn't look joyous at all =(...

I have a fern, and it doesn't look joyous at all =( It have a lot of brown leaves, and several websites vote to cut the leaves, do I do this by cutting from the step or the leaves it self or partly of the stem? I don't want the poor plant to suffer any more so I'm afraid to hurt it. Here is the type of fern it is: Adiantum venustum. Please help! Thanks! =)