Alternatively, just use a privacy coin and skip all the work and fees associated with using bitcoin mixers. XMR is one of the best options considering the high trading volume and fairly stable price.
Xmr is also becoming illegal in some countries. Mixers aren't illegal yet, as far as I know.
That is also the point I will try to make, countries like Japan and Korea have ordered exchanges to remove anonymity centered coins like Zcash and Monero as they don't want this cryptocurrencies to circulate around in their country. Bitcoin mixing is the best alternative to remain anonymous with your transactions, I consider this a loophole in the system and IMO I think that this can still pass on future regulation and international services like this cannot be controlled by one country alone.