How to use Sudoku Wallet to mix your coins
Press "New Sudoku" to generate new sudoku Wallet. You will receive your wallet key to access it. Save it, or write it down somewhere. If you lost it, you can't open your wallet.
You must add Bitcoins to your deposit address, wait for 3 confirmations then press "Mix my coins!". Using just 1 output address is not anonymous, so your coins will be split random between 2,3 or 4 addresses. You will receive clean coins, pre-mixed with CoinJoin, which haven't any connections with your deposit coins. Then you just should grab private keys, and import in your own main wallet.
CoinJoin Fee = (Number of Output addresses x Transaction Fee) + Random Fee 0,5-1%
In other Mixers you send your money to unknown address. In Sudoku Wallet you control your coins by private keys from all addresses in wallet.
Of course you're not. You must carefully check everything and make decision by yourself to use or not.
You can do it in Electrum wallet, or Blockchain.com, or BTC.com. For example, Blockchain.com can propose you to transfer coins from imported private keys to your wallet.
It's very important to delete wallet after every CoinJoin. Please generate new wallet for every mixing, to get strong anonymyty. In your wallet you can find button Delete, in the bottom. Warning: this action can't be undone.