Let's say you have $100 and you decide to allocate 5% of your portfolio per trade. If you take a long trade on Bitcoin (BTC) at $28,000, and the price drops to $27,200 or any lower value, you can implement DCA.
With DCA, you would open an additional trade at the lower price, investing another 5% of your portfolio. This means you will have invested a total of 10% of your portfolio after implementing DCA.