We generally recommend applying scalp oil treatments before your shampoo but you can also try to leave the treatment overnight on your head and wash the next morning. Each scalp reacts differently to oils. Some people never use oil on their scalp at all and others can leave it for 12 hours with great results. So I would recommend to test and monitor closely how your scalp feels and if you seem to have more or less hair loss using this treatment. Then adjust based on your observations. For a safe start, you can apply the treatment for around 30min before your usual shampoo, massage it gently to make sure that it’s spread everywhere on your scalp. After 30min, wash your hair as usual. If you want to test adding it a little every day, make sure you use really small quantities and that you monitor closely your scalp ‘cleanliness’ level and make sure you don’t keep it oily/dirty for long as it would have bad effects on your hair loss as well. There is a fine balance to find but once you know what your scalp likes, your progress will explode ?