I think you’re letting yourself be intimidated unnecessarily. It sounds like you already have a lovely sense of what Christmas means to you, and all you have to do is let yourself dc experience the joy of it all, through you.
Be a little choosy about what you add. It can get very stressful, very quickly. Between hosting difficult family members, staying up late until dc are finally asleep to set out the Santa gifts, only to be woken a couple of hours later, or blighting the entire month of December with that fecking elf.
When the dc were small we just did a Christmassy version of what they usually did. Christmas crafts instead of normal crafts. Christmas baking instead of baking, Christmas story books. We collected pinecones on our walks or went to see the lights on the houses in the neighbourhood. I bought a nativity set that they could handle and as they learned more details in school we added extra figures (more sheep, shepherds, Roman soldiers and a weird cast of extra animal visitors)
Every year I bought a tree bauble to represent something about their interests, personality, development, or just the one they chose themselves. I pack them away in their own container, so we can take them out together each year. We also bring a souvenir from places we visit so that over the years the Christmas tree has become the story of our family.
Traditions will happen, without you realising. One year you’ll order pizza on Christmas Eve for convenience and boom! forever after it’s a thing you do! When ds was 2 he “helped” granny put up her tree and after 2 mins wandered off to watch cartoons and eat a chocolate biscuit. The following year, he was looking forward to putting up granny’s tree and eating chocolate biscuits. She’s still buying their special packet of chocolate digestives every year. Those kind of things persist long after they’ve given up the Santa visits.
We came across deer out on a walk one year and they ate some apples we had. So that year, I made a bit of a fuss about the fridge being full, and said I’d leave the veg in the garden instead, and then pretended that Santa’s reindeer had eaten up all our vegetables, Every year after that, we’d leave carrots somewhere different only to find they had caused mayhem (muddy hoof marks on dad’s clean car, sleigh marks on the lawn and mum’s prized plant squashed, furniture knocked over etc). Finding out what the reindeer got up to was one of the highlights of Christmas morning.
One year dd read Beatrix Potter’s Two Bad Mice on repeat, so that December, we put two little mice decorations into our doll house, and bit by bit across December they decorated the dollhouse.
On the practical side - when the time comes, get your dc to write a letter to Santa as it helps avoid last minute changes of mind. And buy two identical stockings, so that you can fill one and do a stealthy switch. Don’t ever buy a stocking with bells on!!!
But this is all a way off yet. For now, just enjoy it all.