Best practices of Bitcoin mixing in 2021
This is not "best practice". It is basic rule of mixing.
Separate unmixed and mixed wallets
If you are importing or sweeping mixed funds into same wallet as your unmixed funds then sooner or later your wallet will join them. Keep separate wallets. If it helps - use different software for both.
Active wallets require periodical mixing
Mixing may erase your on-chain history but if you are making multiple transactions with multiple people your new history grows. Pick reasonable number and mix your used funds after. Do not mix unspent chips - they have no history and you will get better privacy this way.
Delay your withdrawal
Your deposit transaction is recorded on-chain. If you withdraw instantly especially large sum or unusual combination of chips at once then it can decrease your privacy. On the other hand if you keep some time between receiving chips and using private keys then your privacy grows with each ChipMixer deposit and withdrawal.
Plan your chip size
You know you will pay 3.5 mBTC every week. You mix 12 mBTC and receive 8 mBTC and 4 mBTC chip. If you withdraw them like this - two of your transactions will be linked. It is better to split 8 mBTC into two 4 mBTC chips to have them ready for each payment.
Change handling is dangerous
You spend 2.5 mBTC out of 4 mBTC chip. Then 7 mBTC out of 8 mBTC chips. You have 1.5 mBTC and 1 mBTC change outputs. If you join them - your previous transactions will join. If you keep them - sooner or later your wallet will use them and you will not know when.
Use cryptocurrency services that allows you to create multiple deposit addresses to join them off-chain. You can also send them to ChipMixer separate sessions to withdraw them as chips. Just remember that minimal value is 1 mBTC and sending between 1-2 mBTC will give you only 1 mBTC chip and donate rest.
Try to keep chips out of wallet
Bitcoin wallet is the best place to keep Bitcoin private keys but sometimes it is not. For example Electrum thin-wallet will ask server to fetch your transactions disclosing all public addresses. If you keep chip private keys out of Electrum wallet till you want to spend them - they will not be known as owned and withdrawn till then.
Do you disagree with one of them? Do you know something better? Contact us at firstname.lastname@example.org with topic "Bitcoin mixing - best practices".