Magic Tricks

First of all, there is indeed memorization involved, as well as a little mental mathematics if you do it Daniel's way. It is well-taught and clearly explained, and there's a possibility you may already know the mental math needed for this as it uses the method of a well-known gaffed deck. That being said, it's a little stilted as well because you need to handle the deck at one point to spread it. Also, the deck can be cut face up but not shuffled at any point, meaning you'll need to either do this standalone or switch the deck in.

I think this is a good starting point if you haven't done anything like this before, but if you are familiar with other stacks you might find it easier to use those instead. Also, the lack of marked cards is strong because they keep the cards they chose covered until you call each one, yet you could still use marked cards and just glimpse the next card in their hand as they reveal the top one to be a correct guess. That would eliminate the need to keep the deck from being shuffled and seem more casual.

In other words, there are a lot of ways to accomplish this effect and that's what makes this easy to personalize. Even if you don't use Daniel's method and find a more comfortable way for yourself this is still a good foundation to build upon. You can really lean into this as a mentalism routine when you're confident with it. I won't use this as is but it has given me some good ideas.