All three groups might be relevant to you at some point in your career. It pays to keep in regular touch with your inner circle of advocates and touch base with your allies every six months or so. You could put reminders in your calendar or set aside a couple of hours once a week to catch up with anyone you haven’t been in touch with for a while. Try to think of something to tell them, or send to them, that’s related to their job or one of their interests. This will remind them of your existence and how nice and helpful you are.

It may be useful to maintain relationships with business associates in your outer circle as well. This can be done by following them on social media, 'liking’ content of theirs that appeals to you, making occasional comments on their posts and re-sharing their content if you believe it might be relevant to your own connections. However, don’t be tempted to endorse or share content indiscriminately, as this could damage your reputation and encourage your followers to ignore your posts or cut ties with you altogether.