Here's a fragment of a directly-created epub. First the xhtml, then the associated style-sheet. It has a header style for chapter headers (which Sigl's TOC-generator will pick up) then just standard book styling - an un-indented first paragraph, no paragraph spacing, and a style for a section break. That's all you need for the average novel.
Compare this code with the sort of mess you get from a "conversion" :-)
<?xml version="1.0" encoding="UTF-8" standalone="no" ?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"><html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title/>
<link href="../Styles/Style0001.css" rel="stylesheet" type="text/css"/></head>
<body>
<h1>Stuff to do</h1>
<p>I hope you are both well. Blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah</p>
<p>I wonder if we could make a few changes to the Oaks
website. Blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah</p>
<p>Initial page flyer: could you please take off Easter dates
at the bottom. Blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah. Blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah</p>
<p>Replace the prospectus application forms for holidays
(<i>Stepping Stones</i> and <i>Activity Centre</i> can have the same)
with the ones attached -
e.g. no Easter but Summer and Half Term</p>
<p class="p1">Thanks Jane</p>
</body>
</html>
<<<<<<<<<<<<<<<and now the stylesheet>>>>>>>>>>>>>>>>>>>>>>>>
p {
text-indent: 1.4em;
margin: 0;
}
h1 + p {
text-indent: 0;
}
.p1 {
margin: 1em 0 0 0;
text-indent: 0;
}