When you sign up as an 'employer' you will be asked to set up your profile, of which one of the steps is setting up your email signature.
You will simply copy and paste your email signature from your email into the signature box and click ‘ADD SIGNATURE’
If you skipped that when you signed up, you can easily update it under your profile section:
1. Click on your name on the top right hand side of your dashboard and click on ‘Profile’
2. Click ‘EDIT’ on the ‘Email Signature’ box:
3. Paste your email signature and hit ‘SAVE’: