Gregg, On the edit page, select the category tab above the biography area. In the text box that appears, type titanic. There is an option for: [[Category:Crew of the Titanic]] I inserted this for you. I also added the sticker for Titanic crew:
{{Titanic Sticker|Crew}}
You can find additional information at the Titanic Project page https://www.wikitree.com/wiki/Project:Titanic