If you're talking about guessing the actual opening price - then...

If you're talking about guessing the actual opening price - then no one can really do that.

You can see the indicative price during pre-opens based on the buy and sell orders placed. As these things can change instantly, it's also a game that can be manipulated so take any indicative price you see this far out with a grain of salt. Once we have the full announcement, then things will start.

All the buys and sell orders are matched and the opening price is determined. All buy orders above this is executed and all sell orders below this is as well.