Don't have a mentor? Find one! Someone that you trust and respect who has been in the business for awhile. Approach them and see if they would be willing to take on the role ... most likely they will be flattered.
If you are lucky enough a mentor will find you. Twenty plus years ago my mentor found me. I had been working for her for about a year when one day she asked me to come into her office. She told me to sit down and then she shut the door. Very seriously she sat down and said to me "you were made for Human Resources." It really had not entered my mind but after some thought I realized she was right. It was an area tailored made for me. She helped me to set goals which with alot of hard work started me on the path to success. In later years when I needed guidance she was there for me. Without Pat I may never have enjoyed such a rewarding career.
So if you don't have a mentor ... you should find one. It will be one of the best career moves you make.