Cute little sky (obviously a pet name)
From the Sierra Morena comes a pair of little black eyes --
Cielito lindo, carrying a grudge (it says "of contraband" literally, but this is idiomatic)
REFRAIN : Ay, Ay, Ay, Ay, Sing and don´t cry, Cielito Lindo, because singing warms the heart
If the bird that abandons its first nest finds it occupied upon returning,
Cielito lindo, then it´s getting what it deserves.
And that little mole you have next to your mouth --
don´t give it to anyone close to me (Don´t kiss my friends, I believe is what he´s saying)
Of course, the song can be translated many, many, ways, but as with any poetry or music, you can never recapture the beauty of the original language. Anyway, the song is about a girl who dumped this dude and now she wants him back, but he´s taken and he´s happy with his life. He tells her to quit crying and just sing, cause singing will make her happy. I think he´s trying to be a bit facetious, kinda like saying "I´m happy now after you broke my heart, now what´s your problem?" or "now you see how it feels". Whatever the case, the singer is obviously having fun with this. This is perhaps one of the best-known folk songs from Jalisco, or from Mexico in general. It´s an awesome little song, perfect for drunken sing-alongs, or just having fun.