Big picture stuff - ability to oversee the efficient and effective operation of the team and support that team with whatever means possible.
Small picture stuff - your personal assistant. Trust me they are this personified - if you do not have one that can do this - sorry - get another one.
Keeping up on details, informing you of the dozens of details that have escaped you, saving you the same dozen times from the infidels that would like to waste time, energy, lose focus and destroy you...:)
Don't think that personal assistant day is the only day that you should thank this wonderful person in your work life. Champion their cause, make sure that the working conditions are pleasant and they they have decent equipment.
This individual should present themselves as a reflection of the same type of servant image that you are expected to exhibit. They will be an essential part of the team, so make sure they are pleasant and even-tempered. Best part, they should view working with a team of people - even difficult people - as part of their ministry.