In Germany, it is customary to greet people with a strong handshake. The more Mediterranean cultures go in for kissing - although even this is not necessarily standardised. Even in France it differs by region as to whether the norm is four kisses or two. I am told the Polish compromise with three. Eskimoes rub noses (or is that one of these horrible stereotypical myths?)
What, however, do the British do? Some friends I hug. Others like to go in for air kissing (differing numbers thereof). Some very good friends are not really the kissy type at all and are merely greeted with a cheery "hello".
Trying to remember who likes to do what - for want of a better phrase - can be a bit of a minefield. Invariably it all descends into an awkward shuffle, much blushing and apologies.
Maybe that's the answer. If you meet an English person, just greet them by saying Sorry.