We cannot overcome panic and greed. But we should develop strategies and implement them before trading. This allows us to not panic when placing orders.
In my opinion, the best way to get around the problem of "greed" is already that we buy in "batches" and preferably at fixed times, for example every Monday at 0 o'clock. In this way, we certainly never (or at least almost never) buy at the bottom, but the probability that we make bad purchases (buy at the top due to FOMO, ...) without a corresponding strategy is very high - and to be honest ... most of us know such "FOMO-situations". At least I do, I still have XRP in my portfolio which I bought at way above 2$ ...