CKEditor's Add-ons list is full of very useful plugin, but the most of them require a FileBrowser, eg: CKFinder. I think these are too uncomfortabble, and too complicated, so I did the most simple image upload plugin for quick image uploading. I hope it'll help you!
The recommended way to install all CKEditor add-ons is to create a custom build by using Online builder. To do that, click the Add to my editor button on the plugin page. When you are done, click the Build my editor button on the right side of the page to go to Online builder.
Note: This add-on is already selected to be a part of your current build.
Add-on installation instructions
If you want to add the plugin manually, you will need to:
Extract the downloaded plugin .zip into the plugins folder of your CKEditor installation. Example:
The most easiest way to upload images to your webserver. First of all you have to add plugin into your editor and you have to add an upload url in your config like this: