In belly dance there is so much to learn - even within a single style. It is a chance of lifetime learning. The first challenge most people face is actually taming their body. Learning that hip figure eight that does what you want it to do - staying horizontal or vertical or doing a combination of both and keeping it smooth. Getting a shoulder shimmy that moves only the bits you want to shake.
What might surprise many beginners is that "getting you body under control" doesn't really stop. You just add more difficult moves to your repertoire. (Not that belly dance is about having to master more and more difficult moves - but you don't learn it all when you can execute a flawless set of isolations on each part of the body).
For many people the next step is learning movement combinations, layering and transitions. Some then start collecting choreographies. Some then challenge themselves with improvisation. Both are valid. What both are working towards is learning to interpret the music - within the belly dance genre.
This step requires some outside assistance. Although a dedicated and talented person might be able to learn the moves, it is much harder to learn to belly dance. For this you need a teacher - or even better a number of teachers. Some may be people you attend class with. Some may only drop in to take a workshop. Some you might learn from by watching their performances. Over a period of years by watching good examples of the dance and being corrected by knowledgeable teachers you extend your ability to be able to be a good belly dancer yourself.
A student of belly dance (and by that I also include the best teachers) also needs to understand the different styles within the dance. They don't need to be able to do them all well but they should be able to recognize obvious examples of (say) modern Egyptian style, Lebanese style, old style Turkish, AmCab etc. They should also have an idea of a couple of major folkloric styles from the area of interest - Egyptian folk for Egyptian dancer, Turkish or Rom folk for Turkish dancers etc.
Another aspect of the dance is a range of props. A basic set would include veil, zils and cane but there are many others – again depending on the style(s) you are interested in - sword for AmCab and Tribal, shamadan for Egyptian, spoons for Turkish. A belly dancer needs to know not only how to use them but when to use them. What music works. What movements go with them.
Then there are cultural factors. A dancer needs to know about what his or her music means. Not only what the lyrics say (and many instrumentals also have lyrics) but what it actually means and also what it means to the audience. For instance some very upbeat songs can be about loss. And some songs are metaphors – for example there is a song which appears to be about a man’s mother but is actually a political song about Egypt. For Egyptians songs by Oum Kalthoum have a particular significance and need to be treated with sensitivity.
So, some understanding of the language (whether Arabic, Turkish or Farsi) is useful. But an understanding of the people’s culture and history is also important.
One problem with self taught dancers – or those that do not have a good teacher – is that you often cannot know what you do not know. Experienced belly dancers are forever stumbling across people saying they have learnt it all (after a year, two months or whatever) so have had to branch out into fusion or burlesque or whatever. They shudder – but often it isn’t the dancer’s fault. They often truly don’t know they are missing 90% of belly dance.
So, if you are feeling a little too smug. Look around and find a new challenge within the dance. After 19 years I’m still learning new stuff – and I really only have a deep knowledge of Egyptian and generic belly dance.