Can't be a DCO without a degree. Most DCOs have several years work experience in their field as well. Enlisting in the Reserves is as easy as regular active duty. The min age is higher though, I think it is like 23 or 24. If you intend to apply for OCS from the Selected Reserve after you get your degree the process is just the same as for civ guys. See an local officer recruiter. They will have your CO sign some forms and they will request your enlisted service record from the Reserves. If you want to go DCO as a selres officer from selres enlisted, that is harder. Like I said, most have significant experience in their field. Not something most recent college grads have. Unrestricted Line Officers like Aviation, Sub and Surface officers cannot be DCOs. Check out the posts in the Reserve forum.