the absolute best tip I have learned in my car detailing job, is for cleaning cloth seats...

just fill a wash bucket with soap and water (car was soap -- none of that wax soap though) ... dunk the mitt in, and then twist and squeeze it until you ahve most of the water/suds out of it, and it is just pretty damp... then scrub the hell out of the seats. I have never ceased to be amazed by how clean the seats come... it will usually pull out stains too! like 95% of the time, if you rub hard with the mitt on a stain, it'll come right out.

And yeah, spray 9 is pretty good... albeit somewhat aggressive, I think (though I have never used it, my buddy swears by it).

I use a citrus degreaser that is not available in USA... there are lots out there though.

 

looks just like mine