I suggested that she should look at each event in the tree, search for each source, and add the events to her tree, and add the sources for the events in her own tree.
However, she wanted to just source the online family tree. So here are two examples of a source citation for a person in an online family tree found by searching online. I used the Evidence Explained templates for a person in a Documented Family Tree in RootsMagic 7:
1) A personal family tree, for instance an Ancestry Member Tree:
The finished source citation for an entry in an Ancestry Member Tree is:
"Ancestry Member Trees", indexed personal family tree databases, Ancestry.com (http://www.ancestry.com : accessed 9 June 2016), "Randy Seaver's Genealogy - July 2014," Frank Ellsworth Seaver (1876-1917) profile; submitted July 2014 by Randall J. Seaver, [contact information for private use], Chula Vista CA 91911; Web: http://person.ancestry.com/tree/71134866/person/42230724112/facts.
Source citations for profiles in other personal family tree systems (e.g., MyHeritage, Findmypast, WorldConnect, etc.) would be similar - just substitute the family tree name, the profile name and other identifying information.
2) A universal family tree, for instance a FamilySearch Family Tree profile:
The finished source citation for a profile in the FamilySearch Family Tree is:
"FamilySearch Family Tree", indexed universal family tree database, FamilySearch (https://familysearch.org/tree/ : accessed 9 June 2016)," Frank Ellsworth Seaver profile KH28-Q95, last updated 22 October 2015; submitted by Randall J. Seaver, [contact information for private use], Chula Vista, CA 91911.
Source citations for profiles in other universal family tree systems (e.g., Geni.com, WikiTree, etc.) would be similar - just substitute the family tree name, the profile name and other identifying information.
Copyright (c) 2016, Randall J. Seaver