Submitting Plugin to WordPress.org

Submitting plugin to wordpress.org repository is a cautious as well as watchful process. Before submitting, one must have readme.txt and license (GPL 2 or later) in the plugin folder.

The plugin folder structure depends upon the coding style of the developer so it can be of different type. But, an important thing to note is that there must be the two files: readme.txt and license.txt. A standard readme.txt file can be seen in: https://wordpress.org/plugins/about/readme.txt. Before submitting plugin, one can even validate the plugin readme.txt at: https://wordpress.org/plugins/about/validator/. Also license can be generated from: http://www.gnu.org/licenses/gpl-2.0.html.

Plugin is an integral part of WordPress and hence it needs careful testing before submitting. It must function as intended and must contain proper WordPress coding standards. Another important thing is dependency. Don’t include the styles or scripts from outside link or from CDN. All the third party styles and scripts must be included locally in the plugin.

Now, after considering all of the above facts, lets see how to upload the plugin.
First, keep the zip archived file of the plugin in any link, but must be directly downloadable. It means, after hitting the link, the plugin zipped file must get directly downloaded.
Then, upload the zip archived file at the WordPress.org directory from: https://wordpress.org/plugins/add/. After successfully uploading the zipped file, wait for your turn to get your plugin reviewed from Plugin Review Team (WordPress.org). If the review team finds any sort of bugs or loopholes, you will receive an email with the feedback. But if your plugin is approved, then you will get plugin hosting requests approved email along with some handy links. Now, upload your plugin to the given SVN repository and you are done.