Using the WordPress Plugins menu page.
1) Open the WordPress Plugins menu, select "Add new plugin" submenu
2) In the search text field enter "booking" or "booking calendar" term and select search.
In the search results, find "Booking Calendar" (created by wpdevelop) plugin and click on "Install" link. Wait until the plugin is downloaded and installed.
3) Open the WordPress Plugins menu page and click on "Activate".
Wait for the message "Plugin is activated successfully". This is important. Otherwise not all DB tables will be created and you will have an error message.
The plugin is now ready for use.

Installation using the uploading of plugin zip archive.
1) Open the WordPress Plugins menu page, select the "Add New" plugin sub-menu and then click on "Upload Plugin" button at top of page. Click on the "Choose File" button and select the booking zip archive. Click on "Install Now" button and wait for the plugin to be uploaded.
If you will receive message like this: "The uploaded file exceeds the upload_max_filesize directive in php.ini", then please check this troubleshooting instruction.
If you want to upload the booking zip archive via FTP, then you need to extract the archive content. You have to get at result the booking folder with plugins files. Then upload entire this folder to ../wp-content/plugins/ folder at your server.
2) Now open the WordPress Plugins menu page and "Activate" that plugin.
Wait for the message "Plugin is activated successfully".
The plugin is now ready for use.