When to get married?

My boyfreind (fiance) and I have been engaged for many years now and we are unable to make up our minds about marriage. We are both madly in love with each other and have a very special life together (as people comment on all the time) and even friends and family are telling us to “Get married.” However, when it comes to “When” we just dont know. I mean we both want to get married eventually.. but we are having so much fun just being together and living our lives one day at a time. On top of that we are both currently working on Masters degrees and we dont know if we should wait until we are out of college? I want to take my boyfriends last name but I’ve already earned other degrees that have my birthname on them. Plus all our Financial paper work changes.. I dont know.. should we just get married or keep living our lives the way we always have? Because sooner or later we are going to have to make these changes… its just “when?”