How to remove muffler on 2009 kia spectra?

I really wouldn't. It'll sound like utter sh*t. And it won't gain you much in the way of power for fuel economy, you'll just be making noise. But anyway you should just be able to unbolt the section of exhuast pipe with the muffler, remove the whole assembly and replace it with another pipe length of pipe in the same shape, but without the muffler.