This is a custom tutorial for making your own RCA (aux cable) to TRS end (the same on on your headphone jack).
Why make this? - you can hook up your mp3 or laptop to your surround sound system.
Okay! so let's get started
Why not just buy it in store? - You are always free to do so, but in some regions it is hard to find stores that will sell these types of things, especially if you live in a less urban area. Some stores also can charge a fairly large amount of money for such an easy project. Plus this is really fun and you can feel proud you did something.
Step 1: Get a regular RCA to RCA cable
An aux cable works well too, just the yellow end should be unused since it is for video, and we're dealing with audio.
The next thing you will need is a 3.5 mm jack. I got this by trimming the end off my broken headphones with scissors.