I only wish more Catholics would actually celebrate Advent instead of indulging in secular Christmas hype.
I know what you mean! In my family's household when I was growing up, the wreaths and outdoor lights went up in the middle of December, and some other minor decorations, but we wouldn't get the tree until almost the last minute, and we would light the Advent wreath on the Sundays of Advent, and sometimes on other days. We would also have a "Scripture wheel" that had different prophetic reading about the coming of the Messiah for each day of December before the 23rd, and had an Advent calendar some years too. I wish people who put up outdoor nativity scenes would not put out the baby until Christmas eve.
Catholics can celebrate, do penance, ask for forgiveness, thank God, whatever, by going to Mass.
It's that simple: go to Mass. Ain't that easy for the rest of the world but it is SO EASY for Catholics: GO TO MASS.