When I client tells me that he's into humiliation, the first thing I ask him is:
what is humiliatiing for you? Because "humiliation" is one of those territories where one man's meat is another man's poison. What one finds humiliating and degrading, another one thinks it's an honour. Also, I divide humiliation in 2 types: physical and verbal. I take notes of what they tell me, and design the session according to this mindset. BDSM play (because this is BDSM), is 80% in the mind, the rest are props, it's all about the psychological play. Get in his mind, and you'll have him in your pocket.