I'll show you how to automate Twitter, but you can use any other service.:
Choose source and destination. In my case: Twitter and Evernote.
Step 2 and 3
Confirm your choice.
Define filter for Zapier trigger. I choose hashtag #blog. All tweets with this hastag will be published in my blog.
On this step you should configure Evernote integration. Choose your blog notebook. Zapier can create automatically content and headers. You just need to define filters and add tag published.
Check your trigger.