I have relatives/Friends who were foster care providers. Thank you for providing an important service. I assume you have contacted the agency and gotten clearance for him to go with you. If not, that would be a first step.
As for masks, the best advice is to have a bunch of different types to try. Both different materials and different styles - some people like the ones with pleats, others like the more formed types. Some prefer the disposable ‘surgical’ types pleated masks. Be aware of smells - some have an odor and some of the cloth ones hold the odor of laundry detergent after washing. Using scent free products and airing out help.
Have the masks available for him to see, touch and smell. Also wearing a mask yourself to model.
This link to Harvard Health has a great list of hints.
Also, people have posted they got suggestions from professionals like OT or teachers working with their child.
My youngest daughter is not autistic, but does have many sensory issues. We thought the Disney ones made from soft material similar to T-shirt material would be great, but she did not like those at all. Some people find those are their child’s favorite masks, so you never know.
We found some others from Kohls and some I made myself that she really likes and wears without any issue.
Some people don’t like the feeling of the straps and find ‘ear savers’ help with the felling on their ears. These pictures show some things people found helpful.
Buttons sewn onto a favorite cap to ‘receive‘ the ear straps.
Ear saver that goes behind the neck. I’ve seen crocheted or knitted ones and some made of cloth. I don’t know if anyone on Etsy is selling them right now, but I have seen them there.
