Remember the good times. Get a gathering and few drinks going and all the memories will be flowing out.
I lost my dad suddenly at the end of this September to a massive pulmary embalism, he was only 48. Still finding it very hard but nothing better than the funny old memorys just randomly popping up in my head, just randomly laughing to my self out of blue.
He may not be physically here but for sure he will always be with you, looking over you.
Rip to your dad and condolences to you and your family