Observe the chart and find out the time range for bullish and bearish cycle.
There are people out there who don't believe that bearish cycle can still happen with the presence of ETF and so on but personally I think bearish cycle will still happen but with diminished pullback, basically the dumping won't be that huge.

You can do DCA if you're so concerned, honestly can't go wrong with DCA, if you decide to go all in the result is always whether you gonna make a big profit or a big lose but this lose is just an illusion if you don't realize the PnL.
My recommendation is DCA until you understand about the market and what direction its gonna take, then you can rethink your decision.