I used to be nice when dealing with other people and that seems good, I need to be strict in some situations?

Question

when it is necessary to be, but in fact I find that very difficult, can any one tell me how to do that?

Answer 1

When you hold some responsibilities and develop a passion, you'll just feel a need to be stonefaced and hold your ground against everyone else, including your friends. It's difficult, but as we get older, we simply our lives by just saying no instead of meticulously allocating attention to design the perfect answer.

So if you really wanna learn to say no to people, pursue a goal, work hard at it, and focus. You'll be strict and saying no to others in no time because you'll be saying yes to what you are trying to accomplish.