This link should help:
We have some great science based lawn care tips to use this fall that will make your lawn even healthier in the spring: https://chemistrycachet.com/easy-fall-lawn-care-tips/
This is the best recipe I've found!
One thing many homeowners never consider is that thatch can be interferring with the health of your lawn - especially older lawns.
Thank you for your answer I will definately give it a try.