Once you’ve harvested your plants the maturing stops. Don’t get taken in by the myths about hanging it upside down to control movement of liquid or anything along those lines, that’s simply incorrect. All life, activity and cell development stops once it’s cut down.
It IS true that curing properly can improve the aroma and flavor, but as we’re doing this for medical oil-producing reasons that’s not really a concern. All you need to do is trim off the large leaves (often called the ‘sugar leaves’) and hang the rest somewhere to dry slowly. The conditions should be a little cooler than when they were growing; normal room temperatures (60-70°F, 16-21°C) rather than the 77-82°F, 25-28°C of growing conditions is good.