How you can cheat the casino and how they will find you.

First let me explain that you will most likely be caught doing anything that is hurting the bottom line of the casino and which is in a way considered "illegal". When you find a sure way to gain from the casino and turn the advantage in your favor is when they will come after you.

It can take a long time for the casino to realize where the leak in their systems is. Usually when it starts burning their pockets is when they notice. They follow the money, find the culprit, then they study his gameplay/what he’s done.

Most casinos nowadays use data and depend on it, not just on cameras and floor surveillance. You need to look into the unusual patterns that are hurting your bottom line and draw a conclusion.
There are lots of ways you can still game the casino. You may end up being banned for doing some of these things but it’s a start.

If you find out a slot that can be manipulated in some way: for example, a bonus type of game which accumulates “points”. Usually you lose small amounts and change your betting to higher amounts and trigger the bonus round on the higher bets. This is not 100% proof but something that can ban you from a casino. You can also lose a bonus amount to accumulate the slot points.
Loyalty programs can be abused also. One casino had a loyalty program for betting money. And a particular poker slot game enabled people to bet and get a return of 100% of their money. This does nothing but accumulate points for the player who can then use the points for cash or other rewards provided by the casino.

You can also find a bug in a casino game like this guy did:

Finding a Video Poker Bug Made These Guys Rich—Then Vegas Made Them Pay

“The evidence was mounting that Kane had found something unthinkable: the kind of thing gamblers dream of, casinos dread, and Nevada regulators have an entire auditing regime to prevent. He'd found a bug in the most popular video slot in Las Vegas.”

So exploiting poorly designed game mechanics of slot games (newer ones usually would be the ones to target) or finding bugs is the surest way to go. Also finding loopholes in loyalty programs or promotions.