mix your coins properly before you send the money (which mixer?)
There are plenty of mixers available in the market. Go to the service announcement board and find one. Would recommend using Yomix which I'm using at my sig, not a vouch of course. DYOR.
1) When you mix coins, you may get tainted coins
It's false. I was also in the wrong sense but thanks to LoyceV, after a huge long discussion, I'm now convinced that there's no tainted bitcoin like there's no tainted fiat. You never know whether the fiat you are using is from a terrorist or not. What you know is the fiat is accepted by your govt and that's it.