There any home remedies to dry up blisters/make rash of Hand foot mouth disease for my 2 yr old son? Family event Saturday and it Tues. He wants to go

Time! Time is your best bet. It will get better. I suspect by Saturday everything will be getting better! You can try some Hydrocortisone cream twice a day until then.
HFMD. If your child has hand, foot, and mouth disease, keep him or her away from other people during the first week of the illness. Hand, foot, and mouth disease usually goes away on its own within 2 to 3 days, which should be enough for the Saturday event.Topical therapy (eg, equal parts of aluminum hydroxide and magnesium hydroxide [eg, Maalox]) and Diphenhydramine for oral rash, pain symptoms.