Tuition takes place over the internet, using video call applications like Skype or Zoom.
The student and teacher can hear and see each other, and both their computer screens can be shared. For example, I can teach from a PowerPoint and annotate it with a digital pen and the student can see everything I write.
Documents (such as past papers) can be loaded into an online whiteboard where both student and tutor can write. This allows questions to be discussed and solved interactively.
Documents can also be shared through Google Drive (I create a secure folder for each student, which I upload teaching resources to).