You must use with a hyaluronic pen. I don't currently sell the needless pen but you can purchase on Amazon. Pens are a bit hard to explain how to use over messaging. If you purchase a pen please watch YouTube videos on how to use.
I wouldn't be able to know, everyone is different. You would have to try 1ml, you don't have to use it all at once. You can use a little and decide if it is what you want to achieve. Be sure to refrigerate the rest, get it back to room temp before next use. If you want more order more. Yay!