CNET published an article today listing all Home commands. If you want to try something fun later, try some of the Easter Egg commands:
Easter eggs:
"OK, Google, always be closing."
"OK, Google, what is your quest?"
"OK, Google, I am your father."
"OK, Google, set phasers to kill."
"OK, Google, are you SkyNet?"
"OK, Google, make me a sandwich."
"OK, Google, up up down down left right left right B A Start."
"OK, Google, do a barrel roll."
"OK, Google, it's my birthday."
"OK, Google, it's not my birthday."
"OK, Google, did you fart?"
CNET article:
The complete list of Google Home commands so far