1.  Head to your den by tapping the icon that looks like a house at the bottom right of the screen.
2.  Once in your den, tap the edit den icon located at the bottom right of your screen (it looks like a table with a book placed on top).
3.  Place Pets in your den by tapping the butterfly icon on the lower left side of the screen, and then clicking on the Pet you'd like to place. You can have 5 Pets at a time in your den!
4.  Move Pets by tapping the Pet you'd like to move, and then dragging where you'd like it to be in your den. Tap the arrow buttons to rotate your Pet! Remember that Pets often like to move about on their own though, so your Pet won't always be where it is placed originally.
5.  Remove Pets from your den by tapping your Pet when in den edit mode, and then tapping the blue "x" that appears above it. This will simply move the pet back to your inventory, you can always bring it back to play another day!

Read more about what you can do with your pets in these articles:

• What are Pets and how can I get them?
• How do I get items for my Pets?
• How do I switch Pets?