I am just starting learning how to make pixel art using this tutorial to start with

http://www.drububu.com/tutorial/

but I cant figure out how to copy the cube without any of the back ground. and also past it right where I want it.

I think my main problem is selecting the entire cube without selecting anything else. with the magic wand I was able to select everything but the cube, and with the lasso it wasn't able to get everything I wanted and nothing I didn't want.