Top tips:
Make sure there's enough light that they can see your face, get a lamp behind the camera (I'm assuming laptop, if phone make sure it's on something stable so you're not trying to talk and hold it!)
Wear shoes that make you feel confident. It helps out you in the right frame of mind.
It's video so they can't see your notes
have separate pieces of paper so you're not shuffling and have on them the key reasons why they should hire you :
Your skills
Your knowledge
Your enthusiasm/experience
How all of the above will make their team better when you're in it
These notes will mean you won't go blank when asked!
ALWAYS breathe in before you answer a question. It makes your voice sound more confident and means your brain has oxygen-lots of people forget to inhale when being interviewed.
Have a glass of water available and if you need to take a longer pause, take a drink.
Don't be scared of pauses, long silences are awkward but video necessarily often has longer pauses because of the tech.
Remember they are interviewing you because they liked your application so you're already almost there!
Go for it and good luck!