I use this site to make slide shows for my blog;
You can select up to 10 pictures.
For size I select Advanced and type in 360, which is the correct width for the blog.
Speed I usually choose Slower (3 Sec).
Then click Create animation and wait for the preview.
Then left click the Direct Link code which highlights it.
Right click the highlighted code and click Copy.
Now all you have to do is put it on your blog the same as you do a picture.