- Enter Advanced Mode by pressing F12 (or Fn + F12) on your keyboard
- Click the Objects Library button in the top toolbar.
3. Find the object titled, “Floor”. This may be located in a different part of the objects library, depending on which project mat you have open. For example, in Sandbox Challenge, “Floor” can be found by expanding “Sandbox” in the objects library. Object lists can be expanded by clicking on the plus sign (+) on the left hand side of the object.
4. Click on “Floor”.
5. Click the Object Properties button, which is also located in the top toolbar.
6. Scroll down and click “Material / Texture” in the Object Properties window.
7. Click the pencil icon in the lower left hand corner.
8. Click on the picture of the mat, which can be seen on the right hand side of the window that pops up. In the Sandbox Challenge, this picture is a white square with smaller blue, green, red, and black squares on it.
9. Once the Texture Selection window shows up, you may either select a new mat picture from one of the options listed, or click “Browse” in the lower left hand corner to select a file from your own computer.
10. Select your picture file (which must either be in JPEG or PNG format) and then click “Apply”. Click “Apply” once more, then click “OK”.