For Advent:
An Advent Calendar with Scripture quotes and a religious scene (it's a wooden, reusable one). I do put a little chocolate in too (otherwise the kids would just feel that they're missing out compared to their friends).
Lots of cribs around the house (I love a crib). It's the equivalent of Elf on the Shelf in that the figures gradually make their way to the crib. The Jesus figure goes in after Midnight Mass on Christmas Eve/Day. The magi arrive at Epiphany.
I'm organising a reverse Advent calendar in church - collect an item for a local foodbank every day.
We used to do a Jesse tree and I still have the handmade decorations, but kids have outgrown it now.
Don't decorate for Christmas until near the end of Advent. The decorations stay up until Epiphany.
Lots of carol services (parish, parish children, parish youth, cathedral, school).
Confession, fasting, day of retreat & recollection.
I make the Advent wreath in church (two - three times because it doesn't last). I use the leftover holly to make a wreath for home as well.
Lots of stuff in the liturgy - more sober music, no flowers, candles lit on the wreath ...
So plenty of ways to keep Christmas out of Advent. I really love Advent!
We keep a candle lit in the window overnight on Christmas Eve. It's an Irish tradition to indicate that the Holy Family would be welcomed in the house. I don't let the kids have a real candle (they can have an electric one). I have a real one in my bedroom and keep the curtain open to lessen the fire risk.
For Christmas itself I guess it's much like a secular Christmas but with church and prayers on top and no Santa. We do say Happy Birthday to Jesus (it's cheesy but I love it). Dc get one present a day from Boxing Day to Epiphany (as well as multiple presents on Christmas Day): it helps to reinforce the message that Christmas starts on Christmas Day, it doesn't end then, and it also helps them to actually appreciate the presents and not get overwhelmed with too much at once.