Harvard referencing style with Bibdesk

[James Bennett]

I can't work out how to get my references in LyX into the style I want
(Harvard - (Author, Date)).  I'm using LyX on Mac OSX (v10.3.7) with the
BibTeX-based referencing program bibdesk (v0.97.8).  As I am painfully
ignorant, I am not even certain whether I need to change/insert things
in LyX or in Bibdesk.  Can anyone help?