That requires hindsight. The market is frequently irrational, you'd have to know what direction it goes next. Think it's going to stop growing because it just spiked upwards? Think again, it may keep going. Think it's going to keep going because that's the trend up to now? Probably not, it'll drop like a rock for no particular reason.

I took a fun little class once on algorithmically playing the stock market. The take away lesson was that the main public stock markets have so many players, many of which are algorithmically driven, that there's nothing left for easy picking. It's basically noise. Best advice? Go play the algorithm game in smaller markets that don't have as many sophisticated players in them. E.g. some smaller betting markets, things like that. And only with play money, but your retirement money in an index fund ;-).

yes it's noise but sometimes is pink other is brown

Do you mean a timing mindset, where you hold cash until a market index drops a preset amount, and then immediately dump all cash into it, and if it rises a preset amount, you immediately sell all of it?

What would those presets be? Could you model this and see how that performs traditionally?

I think more like discrete functions of capital allocation in timeframes driven by a common trend