Hi there.. yes you can mist them, however i definitely suggest getting a humidifier that does this automatically for you.
While of course in a regular room it might be difficult to bring up the humidity to the preferable levels, it's still better than when it's too dry.
Also in case you do get a tent (which i would recommend), the humidifier can still be used in there.
I have mine connected to an Inkbird humidity controller, which basically starts the humidifier when it get's too dry automatically. I just need to refill the water-reservoir in the humidifier about once a day.
Once you're in late bloom, those 40% ambient would be perfect though!
happy growing!