The best way is to just HODL, 90% of the things that you find about passive investment schemes are scam so don't lose your savings for nothing. And you didn't make yourself clear about when you said rotation like convert bitcoin to fiat and then back to bitcoin? What is the need for it? Just keep buying bitcoin from exchanges and you don't need to worry about the source of funds, it's clean and if there is any tainted coins you can simply point the exchange to take the blame.