Syllabus and course setup 101?

I'm teaching a class of 70 kids for the first time (2nd semester PHD student at a large R1 uni in the US).

I was fortunate enough to TA for this class last semester so I have all the teaching materials from the previous instructor on hand to help.

My friend who is also a millennial instructor says to show a lot of tiktok videos and relate that to theory. Keep pre-class reading to a minimum and rather bring up theory etc in the classroom. In friend's opinion, kids usually have (or make) some time an hour before class - so give them short palatable readings.

These are some thoughts that I've put together. It's a subject I enjoy. Would love to hear from experienced professors on here - what are some dos and don'ts for the classroom? How far ahead did you plan lessons? How did you work on grading scales?

Thanks for your time and happy new semester (year) to everyone on here!

Edit - Much appreciation for everyone's responses, comments, and encouragement. Making notes and taking a deep breath!