I started flying relatively recently so can remember it fairly well!
We are all different (thankfully) so different students can need slightly different teaching styles. Of the several instructors who had major input into my flying, the best for me always found something positive about each and every flight. I was never left feeling deflated and that I had gone backwards and since for me at least flying is very much a confidence game that was really important. One of them often gave positive feedback during the flight - it meant I had no doubt what I had just done really well, and giving it helped him to remember it I think for the debriefing!
The best instructors for me also helped me to relax in the cockpit and enjoy myself, and were prepared to think laterally when I was having real problems learning to land.
But, what relaxes one student might wind another up! Especially jokes - senses of humour are very individual. Tread carefully at first.
Student's needs from their instructors can change. If you think one of your students is getting stuck don't hesitate to suggest they try a few flights with a different instructor.
Try to remember your own ab initio experiences. I have felt that some instructors (especially the real naturals and/or who had learnt in their 'teens or 20s) either never knew what it was like to find anything difficult about flying, or had forgotten. Obviously making out that something is really difficult to do (or do well) won't help, neither does not listening to the student explaining what their difficulties are. Sometimes explaining why one can't do something leads to an 'ah ha' moment where the light goes on - and that applies to all learning, not just flying.
Finally, maybe most importantly, remember you are both there because you want to be, and to have fun. Especially your student should have fun!