Steam cleaning

Whats the best way to clean the upholstery i may have to engage the services of a valeter as the seats on my G/F s car are in a bit of a state does anyone know if they steam clean them
I was contemplating cleaning them myself if i can hire a decent steam cleaner is it pretty easy to do
 
i use a carpet washer it sprays detergent and sucks it out in the same sweep steam can make the fabrics go baggy and lose colour
 
yeah excellent mate. i leave the windows open a crack and the engine runing on demist at ful temperature for 10 minutes when ive done it as it helps dry it out.