I don't know what anyone else here does of July 4th, but one of things that I do, early in the day, before the parades and flag-waving and bbqs and fireworks, I sit down in a quite place and read the Declaration of Independence. It isn't that long and it provides some important reminders about why this country was founded and what it is supposed to stand for.
I highly recommend this to everyone.
"We the People, of the United States, in order to form a more perfect union, establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity, do ordain and establish this Constitution for the United States of America."
Preamble - United States Constitution