The setup screen makes copy trading look like a percentage slider. Choose a wallet, set 10%, and let it run. The missing details live around that slider.
Map the complete behavior
First, define the budget. Is the ratio based on the target's trade size, your balance, or a fixed amount? Those are different sizing rules.
Second, define the allowed markets. A wallet can move into a contract you have never reviewed.
Third, define a maximum entry price and slippage tolerance. An alert that arrives late should not authorize an unlimited chase.
Fourth, decide how partial fills are handled. Copying a fraction of the first leg of a multi-leg trade can leave you with the wrong exposure.
Fifth, understand exits. Does the service copy sales immediately, proportionally, or only after a threshold? What if you already sold part of the position?
Sixth, document fees and wallet permissions. Automation costs and access rights belong in the calculation.
Run a small replay
Take several historical target trades and calculate what your settings would have done at the quotes available after the delay. Include skipped trades and failed orders.
That replay is still a model. It is useful because it makes the rules visible before money is involved.
The target's return is not your return. Your settings, arrival time, and fills create a separate strategy.
Further reading: Prices and order books · Resolution rules · Current fees.
Explore the markets: Open Polymarket (referral link).
A note on risk
Prices can change and positions can lose their full value. Examples are educational, not promises of returns.