The one consistent method I know of would be high-frequency trading to front-run orders, which involves maintaining a moving target of state of the art infrastructure (both hardware and software), including a relationship at the markets so you can get an ultra high-speed connection (I'm certain there are rules with this to make it fairer, but I would assume not everyone will be provided a connection simply due to physical limits).
But I also assume that's not the type of thing parent comment is asking about - Any rational actor with an opportunity to do this would already be doing this after all.
But I also assume that's not the type of thing parent comment is asking about - Any rational actor with an opportunity to do this would already be doing this after all.