C'mon.. the lady asked for serious.. sheesh
I would first make sure my daughter knew just how important she is to me. I keep a journal for her and would continue it, hoping it comforted her after my demise.
After that, I would be sure all of my affairs were in order so as not to leave too much behind for my family to deal with.
Then, I would live each day as if it were my last. Enjoy the small things, maybe take a short trip with my family. Other than this, I don't feel I've missed anything in this life so far and would have no major things to accomplish.