Here you will build the thing.
1. One side. Notice how the red connector is placed, it's like a lock for the exploding part.
2. One of the other sides, pay attention to the yellow rod with greys pointing in.
3. Another view of the body. Notice the grey connector on the top. This is where the pin will attach.
4. Build these.
5. Pin. Like I said before, the thing hanging down is an unwrapped paper clip.
6. Insert the FIRING pin.