Hiding cuts in food tech??

So I have a long food tech practical on Tuesday but I've got cuts all up my arm and they aren't gonna be healed by Tuesday and most people ik in school don't know I self harm. So I can wear long sleeves for most of the practical tho it is impractical, but we have to roll our sleeves up to wash up. I don't want anyone seeing my arms, especially with fresh cuts on. Does anyone have any advice? What should I do if people do notice?