Do you want to put watermarks to your photos in a short time? Well, you can. This can be done easily using photoshop action.
Open the photo that you want to add the watermark.
Go to Window> Actions. A small window will pop up. Click on the "Create New Action" icon. Next, name the action as "Watermark Horizontal" and click "OK"
PS: This action is for all the photos that has same sizes for Horizontal photos. If you have vertical photos, create a separate action.
You'll notice, the small action popup has red sign (appears as recording icon). Your steps is now being recorded by Photoshop. Now, go back to the photo and resize it to your preference (probably your blog photos has fixed width and height).
Add a new layer for the watermark part. This can be text/ image or logo.
Now, go to the pop up and click "Stop". You are now done creating action for all the horizontal photos. If you want to test it out, proceed to step 6.
Open another new photo and click "Play" on the Photoshop Action pop up. Make sure you've selected the top part of the action "watermark horizontal" before clicking on the "Play" button.
That's pretty easy! isn't it? :)