Suggestions for short term (i.e. 1.5 hrs) brain fog management

I am doing a trial return to “work” for 1.5 hours today. By work I mean that I volunteer at my child’s school doing checkout in the cafeteria during lunch. I’ve done it so much in the past that I hope muscle memory will kick in. My supervisor has gotten a stool so I can sit, but it is a lot of sensory input with smells, bright lights, and kiddos talking. Thing is, I woke up in massive brain fog today despite my best efforts to rest last night. Anyone have some simple ideas to help wake up/support the brain for a bit?
What I plan on currently: healthy breakfast, take meds/supplements as scheduled, take 1 tablet Adderall that I have for PRN situations, avoid anything physically or mentally strenuous beforehand, sit outside in fresh air and sunshine for at least 10 minutes.
-Maybe add a grounding meditation?
-Take noise canceling earbuds?
-Wearing sunglasses would be awkward, but they do provide us with school labeled visors.
-Add wearing a mask for the smells?
What other ideas?