As the title says. I need skin colour fondant for boobs on a cake
AI see you are in UK. I would suggest a very small amount of Sugarflair Chestnut. I think it works better than their so called flesh colour.
APink, yellow and brown. Start out with the smallest of dots of colour and add as you see fit to make the desired colour.
I have found that a combination of Wilton's ivory and copper make a really good flesh color.