Quick Primer -- What Should I Look For When Searching Coins?

Title is a bit vague -- but here's what I've been doing.

I own a restaurant, and I deposit the change once per month.

I keep the change in a separate "bucket" until I've had time to search it.

I know the basics (I think, at least,) of what to search for. A quick silver check, then I search the nickels for War Nickels, search everything for proofs, or anything that's generally old (pre-1965 is what I consider "old".) I also set aside anything that has a high shine to age ratio :)

I assume this is a good technique for a beginner, but am not certain.

I found a 1971 S penny the other day, which was exciting.

But I can't help but think I'm leaving something on the table, so to speak.

Any other tips for a beginner on what to look for when searching modern American coinage?

Thank you!