I'm sure some of this was already mentioned, but here it goes...
Read to your children. We set a goal of reading 100 novels to our daughters. We're at #80 and the girls are 13 and 11.
Create some traditions. Whenever either of our daughters lost a tooth, I'd write a letter from the tooth fairy. The letters offered advice, humor, fairy "facts" and even maps to buried treasure they could go dig up. In retrospect, I wish I'd done more creative things like this.
Build things together. Teach your children to use their hands. Clay, crochet, knitting, model building, woodworking, papercrafting, LEGO, playing an instrument, gardening, etc.
Don't rush things. Your young child doesn't need that new gadget or that new app or that new programming language. Stick with blocks, trains, LEGO, puzzles, model rockets, art, dress up, books, etc. as long as you can.
Give your children their freedom and let them fail. Children shouldn't be shielded from the world or from not succeeding. With struggle comes growth.
Always remember, some days of parenting seem to drag on forever, but the years will fly by. Try your best to be present and congratulations!