First, create a Weebly Nudge Button app on Common Ninja.
On the apps catalog, find the Nudge Button and enter the Editor.
When you're done creating the Nudge Button app, click on the Save Changes button at the right top corner of the editor.
If you don't have an account on Common Ninja, you'll have to register first.
When you're ready to add the Nudge Button app to your Weebly website, click the Add To Website button at the top bar of the Editor.
On the window that opens, click the Copy Icon to copy the app embed code. In the next steps, you will paste this code into your Weebly website.
Now, let's head to your Weebly website's editor.
On the Weebly Editor, select the Embed Code element on the left panel.
Drage and place the Embed Code element on your page, wherever you wish the Nudge Button to show.
Now simply paste the Nudge Button embed code here. You will see a loading icon.
Click the Embed Code element you've added to enter the HTML window.
In the window that opens, click the Edit Custom HTML button.
Now, simply paste the Nudge Button embed code in the Custom HTML window.
Click anywhere on the screen outside the Custom HTML window to close it.