The speaker is really tired. He hasn't been feeling too good (Despair is throwing darts at him and there's a civil war inside of him) and he wants Sleep to help him out a little bit. He spends a few lines talking about all the good things Sleep does, before trying to bribe him with some cool gifts (a perfect sleeping chamber, a nice bed, etc.). If Sleep isn't interested in those things, however, he can look inside the speaker and see an image of the beautiful Stella. Perhaps that'll convince him.