(1) In order to change to a new template must first the new one on the local computer downloaded, and there are usually in XML format, but sometimes it's just in a .txt file.(2) After logging in on blogger, select Customize your blog.
3. First of all the existing template backup: select layout, HTML editing, and template download. Change the name to something you find out how 'Temp Myblog 010309', then save it. This takes a few seconds, the file is usually small, 50-100 k. This saves not the contributions that's next.
4. As the next backup of your posts. They must not, save it to reload them, it is only a good idea, prior to major changes. Select settings, then export blog (tab). The posts even exported. Save the file again as something the you as 'exp MyBlog-010309 remember'.
5. You must back up or copy your widgets, the HTML code. Make sure that you use a text editor such as Notepad. I put them all in a file with tabs for each, and a dividing line, which makes it easy to copy them again in the new template. Unfortunately, copy and paste is the only way you can here, one at a time, so it may be hard with a crowded interface with many Sidebar gadgets.
6. Now you're ready for the new template. Back to the HTML editing, and select Browse to find the new template on your computer. If you select it, click OK, and if in Blogger again, select upload. The new template will be transferred to blogger.
7. After the upgrade, you will see a list of the widgets on the left side, which are deleted, such as 'html1' and 'blog1'. If you go from here you continue, you probably get the infamous 'Bk-#' error screen with an error code. You must first the new debugging template.
8. Use to find CTRL-F and search for 'Widget Id'.
9. If you a find, then click close, then edit, that resulting widget name you see should be changed by incrementing the number, such as 'html1' in 'html2', 'text1' is 'text2', and so on. It can be two or more of each of these, they all change. You don't change 'blog1', 'blog2', which is almost always present. Then use CTRL + F again for the next instance of 'Widget ID'.
10. If you all have edited it (and make sure cycle, not through it twice), click on Save template. After the dialog refreshes, you have a new list of widgets that will be deleted, but now it is OK, not from the new template.
11. Click on confirm and save. This should now properly, and you can select Preview or view blog and see the results.
12. You can copy now back (individually) your widgets, deleted on import. Even if you have many, it should take less than an hour.
As you correctly backed up have a problem with the new the previous template if there is or you don't like it, you can use back to the original again uploading process, and select the original template name in the configuration backup. Must you copy back the original widgets again, but at least everything will lose you.
First, create a test blog, then not be afraid try a new template update your blog!