I lost my father, Jack, to cancer in 1981 when I was 17.
However, I take great JOY in knowing that I inherited many of his best traits and thankfully not too many of his 'bad' ones. :)
I don't usually celebrate his birthday, August 6th, but I spend each October 22nd, the day he died, doing "Jack Things" - things that he would have done if he were alive - like reading the Sunday paper, going to a museum, eating chocolate ice cream, etc.
Simple pleasures, sure, but a way to sort of share the day with him one day a year.
If your father is still alive, be sure to reach out to him and spend days doing what he would like to do. You'll thank me for it later. Trust me.
But, if your father isn't alive, consider spending the day doing "Jack" things, i.e. things that your own father would like to do if it were just a normal Sunday. That might be going fishing, that might be fine dining, or that may just be laying in a hammock in the backyard. Trust me, doing your own version of "Jack" things will make you feel closer to your dad. It has, at least, for me.
To the left is a picture of a picture of my dad that hung in his bedroom throughout my childhood. I can't remember how old he is, but he sure is young and full of life, ready to explore the world. That's how I like to think of him.