First off you have to start with what is important to YOU. No matter how petty or large the issue in the end you have to be comfortable with your decision. For me - the selection process took a long time. I went the agency route which meant I had loads of choices - pretty much any agency out there. I lost 5 donors along the way (for a variety of reasons ie not putting a deposit down fast enough, one failing my RE's tests, one having a "hidden" medical issue, one I found out did soft porn etc.) Along the process I went from having the most rigid set of criteria and by the end I had hardly any I just wanted to get the process going! In the end I gave up on someone who looks like me (my donor looks NOTHING like me) and someone with a good educational background (she dropped out of college to have a baby) ... what I ended up with in order of importance to me is:
1 - A great personality and a funny person
2 - Intelligent
3 - A good family medical history. (My family is very heathy and I felt it was fair to want this.) I would look closely at any medical conditions that could be inherited
4 - Attractive- with no strong features (I ruled one gal out who had a big chin as neither DH or I do.)
5 - Around my height (I'm 5'5" and I was looking between 5'4" and 5' - 8" as DH's family is taller).
Since her personality was so important to me - I did a little poking around. I used some awards she had won to figure out who she was and ended up on her facebook page. What I realized is that she was FUNNY, smart, kind, outgoing, devilish ad loyal. And, this was EXACTLY what I wanted in a donor!
I must add that I know not everyone wants to get that much info on a donor (I really had to to be ok with my decision) I did end up finding out unseemly things about one donor (soft porn) which really bothered me (and I had put money down on her already!) By the way she was an Ivy league graduate (for real I checked) and had won a prestigious competition. From what I understood she was pursuing acting and felt that the soft porn along with another unseemly endeavor would help her fund her pursuits. In the end not for me.