My advisor was more like my mentor. He is very open, honest and helpful, which made me very comfortable to express my ideas and also to discuss different issues concerning my academic life.
When an airline asks you to sign a waiver for your guitar just scribble quickly in hard to read handwriting "no thank you" and hand it back. Later if they damage your equipment you can claim you did not understand why they handed that waiver to you.
Drawing on my experience in academia and research, I would advise prospective graduate students to embrace challenges. When confronted with a difficult situation, tackle it directly rather than trying to avoid it. You'll often find that the solution emerges as you delve into understanding and addressing the challenge at hand.
Grad school opens doors! SO many doors were opened up for me just in the last two years of my degree.
Make sure you choose an adviser who is well-known in the industry because they will help you grow quickly in the field. I saw my adviser as a professional mentor and I'm able to go to her with questions about the industry. She has given me so much insight into the future of our professional field which has helped shape my future career goals. Take advantage of all the mentorship opportunities that you can. Grad school is the BEST place for that! Finding mentors when you're not a student is hard. Being a student is a great excuse to find mentors who will be so strategically useful to you, if you take advantage of your time here!
Find what interests you. Many other grad students are much younger than I am and will be entering a life's career following completion of their studies. Looking back, I think it's important to pursue your passion and let the career, money, etc., come from that. During studies, stay on top of things. At the same time, don't neglect other outlets, pursuits, interests: things have a way of connecting in unexpected ways.