Manners are important. Know them. Use them. No matter who visits Windsor Castle (or anywhere else the British Monarch is) they will feel welcome and at ease. One reason is that QE II has done her homework (due diligence) to know your customs and what makes you comfortable. Another is that you will be briefed in advance so you will know just what is expected of you. If it’s good enough for the Queen of England, it’s good enough for you. Manners and etiquette make everyone feel more comfortable. If you don’t have great manners, it won’t matter if your IQ is over 150.