There are a few methods:

Coin join

Swap to a shit coin on an anonymous dex that doesn't require kyc like sideshift.ai and then swap back to btc

Open a lightning channel.

Send utxo's only when doing any of these actions or send to a friend who can send different utxos back.

Never have a change output.

Always spend full utxos only.

When accepting kyc coins never mix then with non kyc coins in the same wallet.

Any washed coins should go into a new ewllet that never had any kyc coins in it.