How can I get custody of my son?

I am only 18 and am entering my first year in college. I have my own apartment ( which I only got in anticipation of my son living with me cause otherwise I would have lived in dorms) and I have a job. The mother and I are not in a relationship any longer and we were never married. She is 20, lives whit her mom, neither her or her mom has a job and both of them are on welfare. I tried to make terms with the mother to agree on some terms that would allow me to see my son more than the traditional every other weekend. I feel that in order to be a legitimate father you need to establish a strong relationship with your son which can not be made every other weekend. We have a court date coming up and I just want to know if anybody knows anything that I can do to increase my chances of getting my son. I love him to death and I'm not just trying to get him to get out of child support but it is sad that the American court system makes it nearly impossible for a father that is not with the mother to have a relationship with his son. HELP PLEASE.