Listen to a WIIIIIIIDE variety of musical genres in your home.
That makes a huge difference down the road as kids seem to internalize what they listen to prior to 2-3yo. Because my DD was listening to pretty much whatever we listened to (Bartok to Palestrina to Judas Priest to Duke Ellington and world music), she finds most music "natural" in terms of rhythm and structure now.
She also had a small but rugged electronic keyboard well before she was a year old. It may have been a Christmas gift when she was about 6mo, come to think of it. She loved it dearly. She loved books with rhyming meter (Sandra Boynton is especially wonderful, as is good old Dr. Suess), and clapping/singing games.
She began playing the recorder casually when she was about two.
