Waiting for a drop is never the right approach. This will make you miss out on buying. You think that if Bitcoin reaches $90,000, I will buy. If it doesn't, then you have missed out on buying. You can continue to buy consistently using the DCA method, so you can buy at all levels. If you want, you can set aside some money to buy aggressively.
If you are going to hodl long enough - you can buy anytime, and be in profit.
As a newbie in bitcoin investment you should focus on long term then you will have enough time to accumulate something nice without over pressuring your self that may lead to some certain mistakes that will affect your investment in a long run , like using your reserve and emergency funds to accumulate just to be aggressive. Which may later lead you to point of relying on your bitcoin too early without you reaching your goal.
You don’t have to wait for the dip you can choose to reduce your rate of accumulating when the market is at peak, and same time increase the rate by being aggressive if the market is bearish orbdiwbc