One easy way to let people know where to find you is to add links to all of your social media sites in your email signature. While you are at it, include your phone number, email address and a link to sig-up for your newsletter in your signature. Do you need to know how to do that?
Watch this brief tutorial on Gmail signatures and Outlook signatures. What I like about creating the signatures in the email platform is that you can modify them to include all of your social platforms by email. In Gmail, you can have up to five email addresses with a different signature for each one. In Outlook, you can create a standard outbound signature, OR a different signature for a reply that might not include quite as much information.
There are apps that you can use as well. Wisestamp happens to be one of them. You can check it out here. Have you found any other email signature apps that you like?