You may be able to see large orders on the order books for an exchange, but sometimes they put an order in to make you think they are buying or selling but then they take the order off. In other words they can be bluffing, so it’s hard to know before it’s too late. Also, you can’t just watch the markets all the time to see when it’s happening so it’s hard to time it.
Yes they can be bluffing, this is why I stopped watching an orderbook. It's too unreliable. The information we want is in hidden orders anyway.
If a huge order is not hidden or split into many, then someone probably wants you to see it.
Yup that's how whales play and with how sudden these whales move their assets, you'd be far behind. That's their advantage or the priviledge of having a very big portfolio.