Congrats for the tattoo internship! The facial details in oils look great, I really like the skin tones. Your hand sketches look great and the practice has surely paid off. On heads though, sometimes in twisted ankles the features look slightly distorted. Watch out for shortening the face in vertical direction especially. Would be great to see you doing to heads what you did to hands, loads of quicker sketches focusing on the structure but it's just a suggestion, I know you're busy. Keep up the good work!