Traditions are a big part of the holidays, so be sure to continue any you may have. BUT it's always fun to start some new ones.
Some things which make good traditions are:
decorating the tree together
telling the story of a special ornament or ornaments
decorating the house or yard together
taking an evening 1 or 2 weeks before Christmas to shop for presents for parents, grandparents, and siblings
taking an evening about a week before Christmas to go for
a late-night (or after dinner) drive to see the Christmas lights on houses all over town (when my boys were small they were always in pj's for this, and it was a special treat to get to drive around late -- after bedtime -- sometimes we headed to a drive-through for a snack or took snacks from home)
having an Advent Calendar your child can mark or a paper chain your child can pull a link from every day to mark the days until Christmas
reading the Christmas story from the Bible at bedtime on Christmas Eve
getting to open 1 present on Christmas Eve (parent's choice)
having a special Christmas Eve meal or bedtime snack
having a special Christmas Day brunch or dinner (We have Pillsbury Danish while opening presents and a big brunch with everyone's favorite breakfast foods -- you choose the menu and have the things your family likes best.)
after Christmas sales for older kids with Christmas money or gift cards can be a great tradition as well