Hand Shake, Qatar

The thing likely to impress you about the Arab is his hospitality.
Always shake hands. When they greet each other after a long absence it is customary for Arabs to kiss on each cheek. An Arab may also keep hold of your hand while he is talking to you after shaking hands. This is a normal custom in Arabia and is a mark of friendship (not sexual allusion).
Your host will indicate a seat. The most important visitor usually sits on his host's right hand in the closest seat. Don't be surprised if someone occupying that position gets up to make way for you. Don't sit in such a way that the sole of your foot is presented to another person.
The right hand only is used when drinking, eating and offering something.
It is customary to take your leave soon after you have drunk the coffee.
I recommend books like 'Simple Etiquette in Arabia', a brief look at such suggestions will save the visitor much embarrassment.
Never call at Siesta time!