Hi Dustin!!! Even though I'm a novice at REI, I actually know a bit about this particular topic thanks to my mom who is a buy and hold investor.
For each of the residential properties that she owns, she writes up her own lease and lists each and every detail regarding rent, pet policies, furnishing policies, decorating and appliances, etc. After all that was done she had it all reviewed by her lawyer.
Now in terms of the rent procedure, one of the properties is actually next door to her and my father's home. She explains in the lease the date that rent is due, usually on the first of each month, and then she specifies that after a certain number of days, there will be a late charge added on top of that rent. My mom can be pretty lenient at times depending on the resident's financial circumstance at that time, but she always makes sure that she is firm in the need for the resident to have the rent money ready as close to the due date as possible.
I think that you can do a bit of both which is explain it in the lease and also make a personal reminder approach to them as the due date comes up. But you definitely want to have that information in the lease for legal matters. Because Heaven forbid that a tenant try to dispute with you if that matter comes up.
Hopefully that helps!! And good luck to you!!!