WORDPRESS: To add a Contextly Siderail module in Contextly, first turn on the Siderail in the Contextly control panel.
In WordPress, go to Settings->Contextly->Big Settings Button->Siderail.
Once you have turned that on and adjusted the settings, go back to WordPress.
Look for Appearance->Widgets.
Then drag the Contextly Siderail widget into the WordPress sidebar module on the right side.
That's it.
If you are working with a custom theme, there is a shortcode that overrides the default placement. The shortcode is [contextly_siderail].
CUSTOM CMS:
First turn on the Siderail in the Contextly control panel.
Second, use <div class="ctx-siderail-container"
That's it.
How could you publish multiple Siderail widgets which display different content on a post (e.g. Related Posts, Popular Products, Related Products)?