From experience:
1. Whether you believe or not, talk to a pastor, priest, rabbi, or other clergyman. If he/she is worth their salt, they won't try to convert you, but they will give you some things to think on that are comforting.
2. Do not isolate yourself. Make it a point to be with friends and family.
3. When the pain lessens, and it will, take joy in celebrating your father's life. I don't know what kind of relationship you had with him, but, if you look hard enough, you will find many things to laugh about, to cry about, and just to feel comfortable about.
4. Understand that he will always be a part of you. You will find yourself thinking, "Damn, I'll have to tell Dad about that" or "I'll have to show that to Dad." When you do and the realization dawns that you can do neither any more; laugh about it.
For what it is worth, I lost my Dad thirty-six years ago. I still miss him and I still do some of the things in #4.
I also give thanks every single day that Dad made me the man that I am. I just hope I am half the man he was.
You have my most sincere condolences. If you want to talk, PM me.
One last thing: Yes, real men do cry and unashamedly.