Here’s a ready-to-post guide for a forum, Facebook group, or study blog. It’s designed to be helpful, engaging, and “hot” (timely/useful) for students using the (the H.K. DSE permitted model).
CASIO fx-50FHII Scientific Calculator Features | PDF - Scribd
The is 50 pages of cold, technical data. But the "hot" version—the one you came looking for—is about application. It is about knowing that Shift + 7 ( CONST ) gives you the speed of light (useless in HKDSE) but Shift + - ( π ) is your best friend.
Shift + CLR + 1 (Setup) + =.