Hi Jie Sheng,
Your skin needs time to heal. Attempting to remove a tattoo whilst it is still healing only increases your chance of scarring. I advise all my patients to wait at least 4 weeks before going for treatment.
In my experience, tattoos that are less than a year old are much harder to remove when compared with a tattoo that has been there 10 years. Your body tries to get rid of the ink as soon as you get it.
Older tattoos means that your body has had more time to remove when compared to a fresh tattoo. This usually translates to fewer sessions required for older tattoos when compared to newer tattoos.