What Publishing?

SO what are the three most common mistakes a new writer can make when wanting to publish something that they have dreamed about publishing?

1) They don’t know about promotion.  There are two things about promotion; too much and not enough.

2) They don’t know the in and the outs of publishing in general

3) They want money and don’t like the idea that it takes time, but that by writing say a blog they can be publishing the work they do.