Being prepared for appointments is something anyone with a serious illness or chronic condition should do. Through my experience with Cushing's, I have learned to look up my test results ahead of time and try to understand what they mean and what that means for treatment, medication adjustments, surgery plans, etc. I also like to go to appointments with a list of questions I have for the doctor or things I want to discuss. I sometimes just keep a running list on my phone so I won't have to sit down and think of all the issues or questions I've thought of since my last appointment.
I sometimes write things down while I'm talking to the doctor so I can remember things I have to do before my next appointment or things to research more. I can always request records of my visit incase I have unanswered questions. Some hospitals have an online medical records system that you can log into and get certain instructions or test results, others you can call or email medical records and either pick them up or get them faxed or emailed. This is useful when you are seeing multiple specialists that aren't always at the same hospital.
One of the best things to do is join a support group, either online or through your hospital so you have people who are going through the same disease. My Cushing's support group can help me decipher test results, and we all have questions about medication and many other issues.
I have created wonderful relationships with the doctors I see most because I don't just sit and listen to them, every appointment is a conversation, and I almost never leave the office with unanswered questions.