Step 1: The Materials
1. Button-top Highlighter
2. A Knife. (or Multi-Tool as pictured)
3. Something long and skinny. (5mm Hex)
4. Aluminum Foil
5. Electrical Tape (Making tape for instructional purposes) (optional)
Step 2: Removing the Guts
Now, there are still more guts in there. You just have to get them out. I found that the best way is to just poke them out the bottom. It's the easiest way. Go outside or over a sink and use some force to push the guts and bottom plug. Ink may or may not go everywhere. Be sure to wash your casing with light soap and water.
Step 3: Making the Bowl Pt.1
The first thing you want to do is to align where you want to place your bowl, or your cap. I put mine as low as possible to avoid facial injuries when smoking. As a rule of thumb, I place the bottom cap next to the highlighter casing where it will sit when placed in the casing. Place the top cap next to the bottom cap. Align the button on the top cap to the end of the bottom cap.
Now, take your knife and ream a hole in the highlighter casing where you aligned it. You want to create the smallest hole possible for the button of the top cap to fit into so the pipe is air tight. Cut the excess plastic off of the edge of the hole in the casing.
Now that you have your hole in the casing, you want to make the bowl out of the cap. Take your knife and gently and carefully cut the top off of the button on the cap. You need to cut about 2mm off to get a good hole in the cap.
Step 4: Completion
Now, your hollow casing can carry stuff too!! Put in some spare foil, tobacco and even some lighters. I generally put electrical tape over the hole in the casing to add some camouflage.
Sit back and enjoy smoking your hand made pipe. Remember, I do not promote the use of controlled substances. My pipes are used for tobacco uses only. This is not a bowl. This is not a bong. Also, heating aluminum and inhaling is damaging to your lungs. Please do this at your own risk.