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

Answer: 
Create a copy of a theme you want to modify - usually a blank theme like [zen](http://drupal.org/project/zen) works well. You'll need to rename the files and fix the .info file.

Then you can edit the `.tpl.php` files. `node.tpl.php` is the main skeleton one. Start copying content from your html template into that file, replacing dummy content with placeholders (which you can find [here](http://drupal.org/node/11812).

Make sure caching is off, and you can refresh to see the changes.
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!