1. Pitch reference: Make sure you know the pitch you need. If your cello is far out of tune and you need to use the tuning pegs, you may have better success matching a pitch you hear rather than following the needle on a tuner (that works well for fine tuning). It's easy to aim for the wrong octave using the electronic tuners and break a string by over-stretching it. I recommend using a piano (A below middle C), your Suzuki, Royal Conservatory, or Cello Time recording, or find the string pitches here (slightly flat , but in tune with each other): https://www.youtube.com/watch?v=ZpN6l0SuNeI
. Or use the drone videos when you are experienced to determine which octave to listen to (A D G C): https://www.youtube.com/channel/UCVI_GbJ5havUqteuAGuEcbQ
2.Use the fine tuners unless the string is so far out of tune that the fine tuner cannot reach the correct pitch. Righty tighty (to raise the pitch), lefty loosey (to lower the pitch).
3.If you need to use the tuning peg, go slowly, turn very little (pluck and listen as you turn, letting the string ring), press in firmly but gently as you turn. Try not to go above the pitch you want. Make sure the fine tuner has room to move both directions, so you can finish tuning the string after you get CLOSE with the peg.
In your lessons I will teach you to tune your cello to itself with no tuner!
But this video is a good guide for beginners.