Read The Bleepin’ Manual
Open Says Me @ SongSelect
Alright, so you wanna raid SongSelect for all those sweet, sweet songs? Cool, cool. When you tap that import button, boom — you're gonna get a sign-in screen. Riveting stuff.
Punch in whatever username or email you use to log into the SongSelect website, plus your password (you know, the one you wrote on a sticky note). SongSelect will then be all like "yo, can OnSong poke around in your account?" & you'll be like "ugh, fine, whatever" & the screen goes bye-bye.
Once you're in, OnSong remembers your auth token (fancy tech speak for "a magic ticket that lets us in"). So basically, you won't have to sign in again... unless your account decides to have an existential crisis & changes status on you. Then you're back to square one, my friend.