Call an old friend you have not seen a long time.

As it is: You always wanted to get in touch with your classmate or your friend, you have taken it very seriously. But there is always something in between. You just do not have time today, so you do it tomorrow. Social media makes it easier these days, but you still have to be proactive. And just imagine that someone would contact you now. The challenge is not that big, just to write an email.