1) theoretically, if you wanted to do something illegal, you just don’t. You just replace $5 or $10 a day of what you’d usually spend on credit card in cash. Every single day, and have your spouse do the same. Every other day, give your kid one of those bills for lunch. Don’t change your lifestyle, just clean it slowly. Use your day job to “save up” a big chunk of clean money. 2) if you just don’t want your IRS on your back, the easiest way is to report “found money” as self employment income and pay your tax on it. They don’t care if it’s illegal, they just want you to pay tax on it. That’s how cannabis companies do it, since it’s federally illegal.