I did this on old MS Office Outlook 2010. I know that it is not actual, but procedure is the same for ages. If you know how to do it on one you can do it on any.
First take File tab and pick Options (Slide 1.).
In next step take option Mail (Step 2.).
Then in the Mail window pick button Signature (Slide 3.).
In next step you have to pick option New under Signature button (Slide 4.).
In New Signature dialog type name for you signature and hit OK (Slide 5.).
In next window type data for your signature and hit OK to save your signature (Slide 6.).
If you have more then one signature choose default signature for your email. Level of customization depends from Office to Office
I hope that this tutorial was informative to you and thank you for visiting this website.