Your not gonna be 100% safe and clear
But there's a few ways to reduce risks when buying precursors ..
*Don't buy all the ingredients for the drug all in one shopping order
*Don't be buying more than a 5 gallon of chemicals in a short time interval
*LIST ONE CHEMICALS ARE THE BIGGEST RED FLAG CHEMICALS ... but a small pint or Liter once in a blue moon should be okay
*Do not give your real name nor your real personal home address
*Do not mail precursor chemicals to the same mailing address where you do your clandestine drug cooks
*If you don't trust your fellow friends with your 17-year-old virgin sister, then don't be telling or bragging to any of your friends about your clandestine drug cooks
*Do not sign for packages
*Do not throw away your laboratory trash in front of your home on trash day .. cops can legally pick up your trash to search for criminal evidence .. throw lab trash at a nearby gas station public trash bin
*Take a look at your surrounding neighborhood ..
.. if you feel anything is off like as if you feel like drug law enforcement is investigating you, then stop stop stop laboratory operation for at least a couple months !! It cost money for law enforcement to sit around conducting an investigation and if there's nothing going on for months then law enforcement investigation will just stop
* Here's another thread on Chemical Acquisition