It appears that Instructables doesn't operate the same way as Blogger.com, so maybe you haven't had problems with this. Just in case, here's the info you need to fix the problem if you come across it.
These are just the quick-fix instructions. I put a more complete writeup on my blog here.
Step 1: Background
The short of it is that Microsoft Picture and Fax Viewer doesn't correctly show the orientation of the picture -- but it lets you rotate the picture so it looks right. What results is that your picture looks right in windows explorer.
However, it's actually now wrong. Software and websites that respect the EXIF settings will "correct" the orientation, leaving you with results that you didn't expect.
Step 2: How to Fix the EXIF
I wouldn't recommend rotating the photos in the Microsoft picture viewer, but just in case you have already done so (or have a picture that received similar treatment), don't worry. The picture can be saved, and quite easily. There are several EXIF editors out there, but not all of them are compatible with all systems (or even have write capability without paying). I found “EXIFeditor” and was able to get it to work.
Find the software here:
However, note the lack of support from the developer:
I had the unhandled exception mentioned in that thread, and to fix it I needed to rebuild my font cache. You should be able to find some links on Google if you run into the same problem, or if you post to this page I can share more details on that. Despite that software not being supported anymore, it fits my needs just fine.
On to the fix:
-Open EXIFeditor and open the jpeg in question
-On the dropdown, scroll down to “Orientation”. Note that it may not be there unless the photo has set a value for orientation. If it has been set, it is likely something other than 1
-Change the value to 1
-Click “commit changes”
Now check your photo will look the same in picture viewer and irFanView , as well as blogger (or other web services). I perform this fix on photos that look upright in picture viewer but not other software, so now it looks correct everywhere.
Step 3: How to Not Have This Problem
And now, the corrected photo, which looks correct everywhere.