I wanted to wire it on my own. I want to make my own SD card reader. I was wondering if I could do this directly to a USB with wires, or if I could use an Arduino to accomplish this. Sorry for not being clear!!
You can't wire an SD card directly to a USB cable.
It is theoretically possible to use an Arduino to allow a PC to read an SD card but it is far beyond a beginner project.
The only practical way for a PC to read an SD card as if it were a thumb drive is to use an SD card reader designed for that. They only cost about $10:
http://www.frys.com/product/6547453