1. Launch the Cat Girl Christmas Decor Game and wait for the main menu to load.

2. Click the "Play" button using the left mouse button to begin.

3. Follow the on-screen instructions to start decorating with Cat Girl.

4. Begin with baking cakes by selecting the ingredients displayed on the screen. Click on the items one by one in the correct order.

5. Mix and pour the batter into the cake mold, then place it in the oven by clicking the appropriate buttons.

6. After baking, choose from a variety of decorations such as icing, sprinkles, and toppings. Click to apply them to your cake.

7. Move on to decorating cookies by selecting shapes and colors. Use your mouse to drag and drop the decorations onto each cookie.

8. Next, help Cat Girl decorate the Christmas tree. Click on ornaments, lights, and other festive accessories and place them on the tree.

9. Finally, assist in decorating Cat Girl’s house. Click on different decorations like wreaths, lights, and snowmen to place them around the house.

10. Once all decorations are complete, admire your festive creation with Cat Girl and her friends.

11. Use the left mouse button throughout the game to select, drag, and place items. Enjoy the holiday fun!