What to use depends on what you have. Applying something may not provide the control you want. The first step in disease control is to work on the soil and make that into a good healthy soil that will grow strong and healthy plants that will be able to fight off disease pathogens without your spraying something.
Take a good, in depth look at your soil to see why you have that problem.

Thanks kimmsr. I mean no disrespect, but the enemy has invaded the fort and I need tactics and weapons to take it back this month. Taking a good long look at the problem may cause me to lose the fort. The fungus has arrived and I need a plan to reclaim my lawn this summer...this month. I have diligently worked on the health of my soil and will continue to do so but I need help in the short term. How do I apply these remedies? The questions I am asking are practical ones for overcoming on the short term.

Milk, raw milk is best, is an effective fungicide and I have used a 50/50 mixture of fat free milk with good success but I've not used milk in a hose end sprayer. You may need to do some math to figure out how much milk to get the proper dilution rate. Most every thing I have related to the milk spray says to repeat every 7 to 10 days, as needed.
If you use all three at once you may get control and not know which actually did that, and you might create something you don't want to. Often when tow or more chemicals are mixed they create something much more toxic then they are individually.
Ground corn is corn meal.