Template:Unsigned

—This unsigned comment was made by User: (talk • contribs). Please sign your posts with ~

Documentation
If you see an unsigned comment on a talk page (or anywhere else where edits should be signed with ), it is generally good practice to check the page's edit history to determine who made the comment, and when.

Once you have that information, you can then append this template to the end of their comment using the code below.

This will produce the following: