The phrase 'speak on how' is correct and usable in written English.
You can use it when you are asking someone to explain or discuss something. For example, you could say "Please speak on how we can improve customer service."
Naomi Wright, a professional service specialist, will speak on "How to Start Your Own Business".
NEW JERSEY CITY UNIVERSITY -- Karen DeAngelis, director of the Women's Center, will speak on "How to Finance Your College or Graduate Education".
NEW JERSEY CITY UNIVERSITY Karen DeAngelis, diretor of the Women's Center of New Jersey City University, will speak on "How to Finance Your College or Graduate Education".
GLEN RIDGE HIGH SCHOOL Dr. Michael Thompson, an author and speaker on the subject of boys, bullying, adolescence and parenting, will speak on "How to Raise Responsible Children".
Many MPs rose in Tuesday's party room meeting to speak on how they thought public sentiment on the issue had changed, and urged the government to change along with it.
He then gathered at the state capitol to speak on how he is the real conservative in the race over incumbent Sen. Mitch McConnell (R-Ky).
(He and wife, Susan, also spoke on how to avoid letting Congress ruin a marriage).
Mr. Hurwood introduced several mystery writers and editors and spoke on how to get ideas for stories, suggesting using enemies.
Tomorrow at 7 p.m., Dr. Mark Hallett of the National Institute of Neurological Disorders and Stroke speaks on "How Your Brain Recovers from a Stroke".
Leading companies spoke on how they are addressing water disclosure and how that practice has evolved in relation to overall water stewardship initiatives in recent years.
Before Gove's speech, he had spoken on how the current ICT curriculum in state schools was simply not good enough.
