follow-the-leader 
(also follow-my-leader)
noun
1A children’s game in which the participants must copy the actions and words of a person who has been chosen as leader.You would have thought I would have learned, but one day after my kiddie afternoon nap, he actually suggested playing a game - follow-my-leader....
- They are sociable and playful, and like to chase, play follow-my-leader and bodysurf.
- Joyuko complained, last again in the follow-the-leader game.
1.1The copying of the actions of others, often without consideration of their suitability for oneself: consumers play follow-the-leader when it comes to buying fashion [as adjective]: a follow-the-leader effect in the investments market...
- The Japanese Prime Minister found himself largely relegated to playing follow-the-leader.
- The best collective ideas come out of diverse contributions, but some groups might have individuals so strong that others play follow-the-leader instead of thinking for themselves.
- But it's not always wise to play follow-the-leader.