Watch the teachers unpick exactly what they will do when the lesson starts. For your situation this may not work and with social distancing you might not be shaking hands. What can you tweak or take from this? Do you have a clarity in how you will meet pupils? Are instructions short? Do you keep scanning and narrating the positives? Do you make it clear what a good start to your lesson is? With no pupils around try and practice your meet and greet. Can you say it shorter? Clearer? How do you transition from welcoming to academic learning?