Short answer
Open the trader's copy settings, switch off “Copy this trader” and save. Nothing more will be bought for you. Tokens you already hold stay in your wallet until you sell them.
Copying also pauses on its own if you hit your “stop copying if I'm down” limit, and the settings screen tells you why. Turn it back on whenever you're ready.
If you had “copy sells” on, stopping also means their future sells won't be copied, so decide how you'll exit any positions you still hold.
See the checks for yourself
Every token on DYOR comes with a rug check, and every trader with what their copiers actually made.
18+ only. Self-custodial: you keep your keys. 0.45% per trade, no minimum. Memecoins can go to zero.