First CNA job..any advice ?!!

I'm starting my first CNA job. I have never done this type of work before. I just have a passion for helping other people especially the elderly and I love love being around them. I'm soooo nervous. The woman is in her late 80's I know I have to bath her, feed her, take her out shopping, swimming and for walks and she has demetia. How should I deal with her? I mean I was trained for this but I need all the CNA's advice out there... please help