I haven't done virtual therapy (my lockdown sessions were all phone only and very short, I've done the same thing for other absences, I followed the points below to some degree for those), but I still have a few general thoughts:
- if it's possible to set up something "shared", that'd be great. Like for example a scent she uses in her office, that she can take with her and you to your spot, so there's still something you both experience together at the same time. Or an object each of you can touch and show the camera.

- if possible make the spot always the same and have it be quiet and private.

- I usually like it to be as comfortable as possible, so for a whole session I'd probably surround myself with blankets, some comforting drink, stuffed animals...