Hi! So i haven't been doing hair very long.. I love doing hair color ,but I just keep getting bleed marks. when I practice on my mannequin I don't get any,but on a real head, I get them in the nape area and on the sides of the head. At work we use matrix. Normally I use vlight. I feel like they slide so I tried folding the foil to the halfway point. Then I folded it again and folded the sides. This helped with them slipping but now sometimes I feel like it came out the top! I'm so stressed out over this. Please give me some advice,tips,tricks. Thank you!!!