Question: I have an HTML template. What are the steps to convert it into a Drupal 6 theme?

Answer: 
There is no automatic way to convert your HTML to drupal theme. Easiest way to create your own drupal theme is to start with Zen theme then customizing the CSS.

Here's a link to Zen theme
<http://drupal.org/project/zen>
I would recommend to avoid the zen theme (which is great, of course) if you already have your own HTML template. It's 10 minutes job:

Create your theme.info file as per drupal.org/node/171205

Now create you page.tpl.php file. Just rename your HTML template to this name. Put these in your header (replace actual link tags for css, js...):

```
<?php print $head; ?>
<?php print $styles; ?>
<?php print $scripts; ?>

```

Now use the variables $menu, $left, $right, $content, etc... where you want to put the appropriate page segments. Do not forget to put this

```
<?php if ($tabs): print '<div class="tabs">'.$tabs.'</div>'; endif; ?>
<?php if ($help) { ?><div class="help"><?php print $help ?></div><?php } ?>
<?php if ($messages) { ?><div class="messages"><?php print $messages ?></div><?php } ?>

```

above the content, so you will get the tabs, help and messages as well.

Style it. That's it. You can have a look at [this article](http://petiar.sk/clanok/ako-vytvorit-template-temutheme-pre-jednoduchy-drupal-web), however it is in slovak language. But from the code pieces it should be quite clear what is going on, if not, use the Google Translate to get more familiar.

Good luck!