1. How to paste the sticker on your friend’s message

First, please go to Prank Friends section, choose the sticker set you like. Then click download

Step 1: In the iMessage interface, select the Sticker Maker icon

Step 2: Drag and drop the sticker you like onto the text line would like to cover

2. How to paste the sticker on your sent message

First, please go to Change Your Texts section, choose the sticker set you like. Then click download

Similarly, you can also drag and drop stickers to cover your sent messages