For me, creating my initial portfolio was horrible because I had to wittle almost 30,000 photos to 20. If you don't have that many photos, you shouldn't have that hard of a time. Pick 50 that you really like, then wittle it down to 35. After that, bring your photos to an art teach or a photographer and have them help you wittle it down to 20. It will be painful but extremely rewarding in the end.