Had great fun today at The Northern Sound System teaching a group to play this song.
Its really not that hard and they were fast learners and we were playing as a band in 2 hours.
Now F Am Dm and Bb Chords are not your standard "first" chords to teach on Ukulele, but you might as well start off on "the good foot" as James Brown would say.
If you play F Am Dm and Bb then you can jam along to the Jessie J video... other people have posted this in more Uke friendly (read easy) chords.. but persevere with the Dm and the Bb Chords and you can sound way more "authentic... plus everybody sings along to Jessie J in this Key so you wont have any trouble makers going "youse is playing that wrong"
So Master F Am Dm and Bb on your left hand and get choppy with that funky right hand. And HAVE FUN