Add tutorial link

app.py

@@ -218,11 +218,13 @@ _HEADER_ = """
 
 # Generate 3D Assets for Roblox 🪄
 Here, you can **generate 3D Assets using AI for your Roblox game for free**.
+
 Some examples of generated assets (video by InstantMesh Team):
 <video width="640" height="360" controls>
         <source src="https://huggingface.co/spaces/ThomasSimonini/Roblox-3D-Assets-Generator/resolve/main/assets/vid/examples.mp4" type="video/mp4">
 </video>
-We **wrote a tutorial to help you generating assets and importing it in your Roblox Games** ➡️ ADD TUTORIAL LINK
+We **wrote a tutorial to help you generating assets and importing it in your Roblox Games** ➡️ [here](https://substack.com/home/post/p-148756528?r=dq5fg&utm_campaign=post&utm_medium=web)
+
 If you like the tool, please click on the like button ❤️.
 
 ➡️ With this tool, you can generate **high poly mesh for your Roblox game**.