There’s an idea around that says no one can touch your Tarot cards but you. I just want to chime in here to say that as with most things relating to Tarot, that’s really up to you.
When I do in-person readings, I like to do the shuffling, but I always ask the querent to cut the deck, then pull their own cards. It feels like they should be involved, it’s their reading after all.
But other people might feel differently. I’ve had many readings where the reader shuffles, cuts, and pulls all the cards. And that’s okay too. My point here is only that there are no hard and fast rules.
If you’re new to reading for other people, just go with what feels right to you. You’ll find your rhythm and develop your own card customs and rituals. It takes time, but the process of finding what feels best for you is part of what makes it fun.
And if you’re concerned about bad energies or weird vibrations getting on your deck, consider getting yourself a crystal, or some stones to sit with your cards when they’re not in action. That’s what I do. Not sure if it matters or not, but I like doing it, and I think that’s the point.
Tarot is more of an art than a set of structured rules … make that art your own.