
1. First you need to create a signature. This can be done in several ways. You can write your signature manually on paper and scan it in your computer, you can use any software like Photoshop to create and design your signature. You can also take the help of online websites to create your signature like mylivesignature.com.
My live signature gives you many options like , design of your signature, size, position, etc. You can take the help of this website to create your signature.
2. After creating signature and saving it as an image, the second step is to upload your signature image to any image hosting site like Photobucket, Picasa, Flickr etc, so that you can get the URl of your signature
3. Now, go to your Blogger account and select the blog in which you want to put your signature. Go to Design | Edit HTML and find one of the codes below. To find, press Ctrl+f you will get search box.
(Note: Take backup of your template by clicking the option 'Download Full Template")
post-footer-line post-footer-line-1
OR
<p class='post-footer-line post-footer-line-1>
OR
<div class='post-footer-line post-footer-line-1'>
Find one of the code above or similar to it.
4. Now, just after the above code, copy and paste the code given below and replace the IMAGE URL with your signature image URL copied from the image hosting site:
<img src='IMAGE URL' style='border: none; background: transparent;' /><br/>
5. Preview it, if everything is OK save your template and you're done!