Savoir Comment

Susan, theoretically you may not need ‘ comment ‘, but it is French as it is spoken by native speakers. There is also disagreement about whether it means the same thing or is slightly different. 

See 2 links below :

My wife ( French) included ‘ comment ‘ when I asked her for her immediate response. 

https://french.kwiziq.com/questions/view/savoir-comment

 https://www.lawlessfrench.com/grammar/savoir-lesson/