Your DCA becomes better and more effective on the lows, I will prefer to use the chart to DCA, there are better times to do this than when the price of Bitcoin is already over its all time high, do not DCA in a full blown top, it is stupid.
You can do it whenever you have money in your hand, and it will accumulate your BTC in your portfolio, as a newbies, if you want to make use of the dollar cost average DCA, it will make you to achieve what you want from bull season.
This is why we have bear market and bull market, DCA when the market is in shambles, when every one is screaming bear market and also use the greed index, this tool is available on coinmarketcap, when the greed index is in full fear it is a good time to start buying Bitcoin.
Bear market is the best season for newbies to make use of this strategy DCA, to accumulate BTC in their portfolio because it will allow them to buy plenty of BTC, but if they make use of bull season, it will be hard for them to buy plenty of BTC because the price of the market will be too high for them which is the reason why newbies need to make use of bear season to accumulate BTC in their portfolio. As it stand now, I don't think majority of buyers will make use of this current price to buy BTC than to wait for the price to dump back to $40k before they can buy and hodl for future purpose.