On the night before, have a good night sleep, place or pack your exercise attire ready. Things you might need for online class includes, exercise mat, water, towel, props like water bottle, cushions, or dumbbells.
Finding a well ventilated, undisturbed space, have your charge cable ready, extra speaker or earphone, connecting your display to a larger screen will be helpful too.
For in studio classes, just bring your exercise bag and show up minutes earlier than your appointment time. Most studios would have everything ready awaiting your arrival. However, be ready to make health and travel declarations during this pandemic period.