Review: WordPress 1.5
The Theme Editor
( Page 4 out of 6 )The theme editor isn't as easy to use as the rest of the WP admin panel, but installing a new theme is very easy on the other hand. All you have to do is upload all the theme files to the wp-content/themes/ directory in your WP directory. After you have uploaded everything, you can just go to the 'Presentation' menu, and select your new theme. Nothing to it.
But editing a theme is a whole different thing. Editing a theme is done by going to the Theme Editor (it's a sub-menu under the 'Presentation' menu). However, before you are able to edit files, you must make sure they are write-able. This means you have to make them write-able, through your FTP program or a file-manager. You have to CMHOD the files. If you need to know more about CHMOD'ing, have a look at http://en.wikipedia.org/wiki/Chmod. Most FTP programs usually include CHMOD'ing options, and make it a lot easier.
After the files are write-able, you can edit them through the Theme Editor. But I personally found that editing these files is very hard. The WP templates have PHP mixed in, which makes it increasingly harder to create a decent style. This is one of my biggest problems with WP at the moment. If you don't know any PHP, it's not at all easy to create a new theme.
Thankfully, a lot can be done by editing the CSS, and in most cases you won't have to touch the main template. But if you want to do a radical change, you have to edit the main template. It will probably take you longer, because of the PHP in the templates. This is definitely one of the downfalls of WP, and should be one of the areas where they make a big improvement. They should do it like MovableType does it, with custom tags. That would make it much easier.