To connect Olark to Zapier, you'll first want to start creating an Olark zap, which will give you a webhook URL in Step 2:
Then you'll log in to your Olark account and select 'Settings' at the top of the page, and from there choose integrations on the left hand side.
On the integrations page you'll choose 'webhooks' and insert the URL from your zap as the webhook URL.
Use the 'Send a Test' button in Olark to make sure that's set up correctly, and to give your zap sample data that will help for later in the zap. Once you've done that, you're all set to continue using Olark in a zap!