When you’re out, tell your lucky one / to know that you’ll leave.
Justin is giving advice on the person that’s leaving him, to warn their ‘lucky one’ that they won’t be around for long.
Don’t you lock when you’re fleeing / I’d like not to hear keys.
This sheds light into the situation itself. He’s saying that for now, he doesn’t want to see the person any more, but don’t isolate him completely by locking the door. Give him hope that there’s still a way to fix this.
Only hold, ‘til your coffee warms / don’t hurry and speed.
You have to let time pass on to simmer down, but don’t jump ahead of yourself and want it all back immediately.
Once a time put your tongue / in your ear, on the beach.
Justin recalls to a time when they both were together on a beach, just them, sex and the simple tides. True love never lets go of the greatest memories in which case this one hasn’t. This simple theme is reminiscent of what Bon Iver is all about: waiting for love to come back.
…and your clutched clicking heels…
Minimal wording but it describes a lot. Although he’s strong against his other, she is dragging him along by his heels. He wants to let go and run, but can’t.