Android MLP Game Question

[Party Cannon 876]

Hey! I just got a new android phone today and one of the first things I did was download the My Little Pony game!

 

It looks real fun. But...I am worried. It states in the description that it may cost real money. From what I understand, what actually costs real U.S. dollars are more bits or gems.

 

It says in the description that if you don't want to spend real money, "You can disable in-app purchases by adjusting your device’s settings."

 

How is this done? I don't want to accidentally spend money in this, especially where a major part of the game is spending money, but in that case its in-game bits.

 

Please help.