How effective is saline removal of a tattoo and can it be done immediately?

Hi I have had my eyebrows tattooed only yesterday but they are far too long. I've complained to the lady, who said she will remove the ends tomorrow by using a saline solution and the same technique as dying them. Can I ask is it too soon to go in or is it best to act fast. Also is there risk or scaring and how effective is this method?