Identical to other email client, you can setup signature in Lotus Notes. However I found out that the graphical user interface (GUI) in Lotus Notes is less user-friendly. It took me a while to figure how to set the signature. Well, here are some simple steps with screenshots on how to configure your signature in Lotus Notes.
1. Go to File > Preferences
2. Click Mail and then click on Signature tab
3. Insert your signature and then tick “Automatically append a signature to the bottom of my outgoing mail messages”
4. Click OK when you are finished
5. Create new email messages and verify if your signature is appended into the email