There are many types of tailored sleeves in men's suit coats. The easiest kind to lengthen or shorten are those that have no buttonholes. If the buttonholes are functioning (meaning that they have been cut open), then you cannot lengthen or shorten the sleeves from the bottom hem. These types of sleeves have to be shortened by taking the sleeves off the jacket and cutting down the sleeve cap.
This tutorial will focus on how to lengthen the sleeve with buttons and sewn buttonholes. (Shortening the sleeves will use the same method, except fabric will not need to be added to the sleeve lining.)
