Expand your horizons

I was invited an English seminar, Judicial System in Japan, by an event organizer (actually it's her side job though, ) Cathy.
She is a member of the Toastmasters Club which I belong. FYI, she is a Japanese! Cathy is her nickname.

After I applied for participating the event, I got her thank-you e-mail.
She wrote, "Please expand your horizons."
I thought it's a nice, suitable message on the first day of new semester!

I want to expand my horizons, and also want to graduate "lazy me!""