As a Medium, I prepare well in advance for upto an hour prior to each reading. This entails, disconnecting from my day and all within my own life to elevate my energy and communication abilities.
Spirit also prepare too. Since your appointment was confirmed, spirit gather their energies in preparation for their opportunity to let you know they are still around and able to connect with your life and those around you by way of evidence. You should also prepare yourself by way of opening up to spirit.
How can you achieve this?
The most important and helpful way you can achieve this is by being honest with yourself and letting go of any anxiety, fear or scepticism you may carry. All these emotions will BLOCK spirit in many ways. Like building a brick wall around yourself.
As long as your intentions are clear and respectful, you should start to put out thoughts to those you hope to connect with and build your own energy up to accept and allow the connections to show.
I am convinced, spirit will only communicate information they feel you either need to know or are ready to hear. Not every detail will be clarified on the spot there and then, which is why I ask you to write as much down as possible. Especially if spirit give future events information.
So, to summarize, relax, remain open minded and calm and you will create a positive and welcoming energy for both myself and spirit to work with to make your experience the best it can be for you.