The best method to extract pure CBD isolate is through what is called CO2 extraction. This method is preferred vs other methods because it leaves minimal to zero traces of chemical contaminants in the end product.
What’s left is a pure white crystal.
Alcohol extraction is another method, wherein a liquid such as ethanol, butane, or hexane is run through raw plant material to extract the CBD and then evaporated to leave only the active cannabinoid. This can be a dangerous method because it’s prone to leaving excess traces of the butane or hexane chemicals in the extract.
Lastly, infusing vegetable oil (i.e. olive oil) is another effective way of extracting CBD. All one needs to do is grind up the raw plant material, decarboxylate (heat) it, and let it sit in boiling (100-deg Celsius) oil for about 2 hours.