One easy way to reduce the size of the images you upload to your WordPress site is to install a plugin called?Resize at Upload.
First, login as a WordPress administrator. ?Then navigate to Plugins > Add New.
Then search for the plugin called Resize at Upload. ?Type that into the box (the way you see it below) and click on Search Plugins.
Now click on "Install Now" and click "OK."
Now click Activate Plugin.
After the plugin is activated, images will be, by default, resized to 600 pixels wide. ?You can change that by clicking on Settings > Resize at Upload. After you make a change to the width, don't forget to click "Update Settings."
Now your images will be reasonably sized!
See the video > http://youtu.be/XtdNoyN0LWc
Resize at Upload's home page at WordPress.org >?http://wordpress.org/extend/plugins/resize-at-upload/