Step One: Does it fit? Nope, toss it or donate it. (if it has sentimental value and you have space, then set it aside for storage)
Step Two: Have I worn it in the past year? No, toss it or donate it.
Step Three: Does it need mending? Yes, set it aside on "the to be repaired" pile.
Note to self: This is going to be an all day project.