​Notice that the first 2 chords G --> B7 can be done with the same shape, just shift the G shape up one string (from strings 123 to 234). How clever is THAT?

Similarly, in the third line, going from B7 --> Em, the diagonal shape shifts from strings 234 to 123.

The last two lines:

C6 - "You" is on the open A string (look ma no fingers!)

Bm7 - "once" is barred second fret, and the melody note is on string 2.

We should play this twice, from top to bottom.