1. First of all, you will need to find the image or layout that you would
like to slice. I'm going to use one from the Professional
Web Host Layout tutorial.
2. Using the slice tool, create your slices that you would like to use.
Things to consider before you slice:
You really need to take into consideration where and what type of content
you will be adding to your design. For instance if you have a large section
in the middle that will be used as an iframe then you will need to make
a slice for this. If you have a box that you would like to add text to then
make a slice where the content will go or you could slice the entire box
and add cellpadding to it in order to get the content lined up right. (If
there is no padding for the content, text will be hard to read when its
touching the border.) Also name your slices accordingly by right-clicking
on the slice and going to edit slice options, as this will help you identify
them later when you are editing the html file.
To see where I made my slices, click on the image below.

3. Now go to File > Save For Web (Alt+Shift+Ctrl+S). Tweak the compression
settings for each slice. For the best compression, use .jpg file extensions
for images with lots of color, and .gif file extensions for line art images(few
colors).
4. Click on the save button to save. Make sure "HTML and Images" is selected
for "Save as Type".
5. Next open the html file that Photoshop just created for you. To add
some content to a slice look for code similiar to the following:
<td><img src="images/slicedimage.gif" width="450" height="300"></td>
Replace it with:
<td background="slicedimage.gif" width="450" height="300"></td>
Then add your content to the slice as so:
<td background="slicedimage.gif" width="450" height="300">
<img src="someimage.gif"><font face="verdana" size="1">text
textContent Goes Here</font>
</td>
You may also find that in order for the page extend as your page's content
increases, you will need to make border images the background image in that
image's <td> attribute as done above for content. (I had to do this
for slices 2, 4, and 6. Click on the snapshot in step two to see where these
slices are.)
Click
here for the result.