The strum pattern is pretty varied throughout the song, so just mess around with it, but
the chords are really easy
Intro: G C G D G C Em D
Chorus:
GCGD
He smiles when she's not looking
GCGD
She daydreams when he's not there
GCGD
It won't be long 'til they discover
GCGD
Ron and Hermione love each other
Verse 1:
GCEmD
He looks at her; she looks at him
GCEmD
And they start to feel the magic within
GCGD
While Harry is fighting He-Who-Must-Not-Be-Named
GCEmD
They talk of the latest Quidditch game
Prechorus:
GC
Someday you'll read(maybe in The Daily Prophet)
GD
About Ron and Hermione(behind the Whomping Willow)
GC
Death Eaters can try to fight(but you know that Ron would save her)
GD
They'd go riding into the night(on Ron's new Cleansweep)
G C Em D x 3
They'd go riding into the night
Chorus
Verse 2:
GCEmD
If Hermione knew the Patronus Charm
GCEmD
The conjured incarnation would be Ron
GCGD
Voldemort is sound; he cannot die
GCEmD
When she's in danger Ron yells, "Stupefy"
G Em D*
Stupefy
Prechorus
Chorus
Intro
*This is a quick change from Em to D