To post a picture to a blog, you need a direct link. I use google chrome as my browser so this is how i do the searches. Google.com and in the search bar, i type anything that i want. I typed Christmas here. Then click on images where the red arrow points.
Click on a pic that you like and it will take you to a page like this.
click on full size image
then at bottome of someones blog click on to comment. Then click on where the red arrow is...
paste that link that your copied from the pic you wanted here...
After pasting that link there, click on anywhere in the light blue area and you will see your pic in that box that says preview...to the left of that box,,,u can adjust your width and height. I usually put in 350 or 400 on width and the height automatically adjusts itself. After that click on ok, then post.