Check out the video tutorial for a quick start:
First create an account at ayrshare.com. Then connect your social media accounts.
Once your accounts are connected you can navigate to the API Dashboard and copy your API key.
Add the Ayrshare plugin via the Bubble plugin marketplace to your Bubble app. In the plugin field "API Key" enter your API Key.
Now you can send posts via your Bubble app to your social media accounts. Learn more about the fields for the post endpoint in the link below.