At first I didn’t worry about humidity for my orchids and they did ok! Once in a while I would spray the air roots with water. Recently, I decided to step it up and try to increase humidity around my plants!
I purchased a mat intended for boots and shoes at Bed, Bath, and Beyond and ALOT of rocks from Michael’s to fill it up! Originally, I purchased bags of medium sized river rocks and found that my plants where often falling over when I set them on top. Later, I added a top layer of smaller river rocks. This really helped fill in the gaps and my orchids no longer topple over so easily! Add some water to the tray regularly and the air should become more humid!