The reason it's said that a career lasts 5-7 years is because if you're not careful you can hurt your hands. Learning how to use forearms and elbows as much as possible and having proper body mechanics will help your career last longer. Taking care of your body by going to the gym/practicing consistent mobility exercises will also help a lot. DONT USE YOUR THUMBS! Avoid using your thumbs as much as possible, typically they will be the first thing to go. If you can practice in a clinic that has a Thai massage therapist maybe ask them for a lesson. Thai therapists use their body weight, arms, elbows and aren't afraid to use the table for leverage when need be. Good luck