diff --git a/4.-Final-assembly.md b/4.-Final-assembly.md
index b6aa305..40cc559 100644
--- a/4.-Final-assembly.md
+++ b/4.-Final-assembly.md
@@ -1,14 +1,35 @@
 ** TODO PIX completed mouse**
 
+In this section, you'll go over how to put the two halves of the enclosure together.
+
 ## Step 1: Get the necessary tools
 **TODO PIX**
+
 - 2.5mm Allen key or screwdriver
 
-## Step : Verify that the Ploopy Mouse is working correctly
-Plug the electronics assembly into your computer. The buttons should be clicking, and if you hover your finger over the sensor, it should move the cursor.
+## Step 2: Put the top onto the base
+**TODO video of assembling the mouse**
 
-## Step : All done!
+You might need to use a bit of force to get the two halves together.
+
+## Step 3: Insert the screws into the base
+**TODO pix of mouse and M3x12mm and M3x6mm screws**
+
+Two of the holes are for the countersunk screws, and two are for the socket cap screws. It should be pretty evident which of these is which.
+
+## Step 4: Apply the friction pads to the base
+**TODO pix of friction pads and mouse base**
+
+## Step 5: Insert the ball
+**TODO pix of ball being dropped into the top**
+
+Depending on slight size variations, you might need to push the ball in with some force, but it shouldn't require a large amount of force.
+
+## Step 6: Verify that the Ploopy Mouse is working correctly
+Plug the mouse into your computer. The buttons should be clicking, and if you move the ball, it should move the cursor.
+
+## Step 7: All done!
 **TODO PIX completed enclosure halves**
 Congrats, you finished building the Ploopy Mouse!
 
-It's done! Plug it in, use it, but don't you dare abuse it!
\ No newline at end of file
+It's done! Love it, use it, but don't you dare abuse it!
\ No newline at end of file