If you have a true Aloe vera at home, cut one leave of it about the length you need. cut it longitudinally in two halves and put them with the gel side on the skin. Fix it with a bandage or so and leave it for hours until its dry.

I once burned really severe, put Aloe as a first aid and went to a doctor to get real medicine. he asked me how big my plant is cause if i had enough that would be better than any medicine he could give me.