Check this thread. Read that and come back to this thread with your new questions.

Like I keep saying around here, mid-summer is the perfect time to begin thinking about proper lawn care. Water: Deep and infrequent. Optimally, you (or nature) will deliver 1" a week all at once (within a given number of hours). Life isn't optimal, so get as close as you can--you can put tuna cans out on the lawn to see how much water you're putting down at a time. Hint: It's probably less than you think. Seed: It depends on your grass. In your locale, you could have cool season or warm season grasses, and they get treated very differently. Please let us know. Weed Killer: If the weeds are green and growing, they're susceptible to weed killer (the appropriate one is key, of course). It's usually worthwhile to start with Weed B Gone and spot spray anything that it'll kill. But let us know what weeds you get as they may or may not respond to 2,4-D, the primary ingredient of Weed B Gone. Fertilizers: Again, this depends on your grass type. Warm season grasses want to be fed now. Cool season grasses don't want to eat until early September (and feeding will harm them in hot weather).

Well I will tell you the easiest, most effective, and in most cases the most economical way. Hire an experience tractor box blade operator to come out and re-grade the yard. It will take them two hours at most and when finished you are set to go. They can even add amendments if you wish. No need to spray any herbicides, just grade it and be done with it. Otherwise you are looking at hours and hours of back breaking work with mediocre results at best. Around here operators get $125 to $150 per hour with two hour minimum. Best money you will ever spend on your yard.

Start with a soil treatment that will soften your soil and allow water to penetrate much better. Your soil is not compacted - it is hard. Those are different. The treatment is to spray any clear, generic shampoo at a rate of 3 ounces (or more) per 1,000 square feet followed up by 1 inch of irrigation. Watch carefully for runoff. Stop watering immediately if you see it flowing off. The soap is supposed to stop that. If you apply the soap, water, and it still runs off, water more slowly. You still need to get an inch on but move the sprinklers and let the water that's there soak deep into the soil before watering there again. Repeat this every other week until you are happy. The expected result will be that the soil becomes very soft to walk on when it is moist. When it dries out between watering, it should become hard again. That is normal. Once you do this, you'll be helping your neighbors soften their soil. This is 100% better than any aeration. It works immediately while aeration works marginally well under the best of circumstances. Earthworms is more of a euphemism for organic matter in the soil. Worms are nice but overrated. What you really need is the beneficial fungi that earth worms feed on. Get going on that with organic fertilizers like alfalfa pellets, soybean meal, corn gluten meal, or as a last resort, corn meal. In the summer heat mow at one notch above the bottom on a rotary mower. When it starts to cool off again, then drop it all the way down. If you really want it barefoot friendly, look for a reel type mower and drop it to 1/2 inch. Contractor grade bermuda is possibly the best turf available, bar none. Why? Because it is so easy for the sod farms to grow that the price has come way down. It is much easier/faster/better for a contractor to put Tif 419 sod down than it is to seed and deal with those issues. There are sports grades of turf around which might be better than Tif 419 but you don't want those. It is never too late to apply organic fertilizer. You can use it any day of the year, rain, snow, or shine. Well, maybe not snow. You cannot over apply, as David_tx said. There is a guy on another forum who applied 50 pound per 1,000 square feet every week of the season with no ill effects. Google "Bermuda Bible" and memorize it. It was written for the chemical minded homeowner. The author comes to the regular lawn forum occasionally and is occupied on other lawn forums. He was a bermuda sod farmer for years and retired last year. At the job he was all chemicals. At home he was mostly organic. After growing bermuda both ways, the bible was written to bring the most success to the most people. David_tx has found a way to grow bermuda organically. Listen to him. Before DNA testing, compost was the only organic material anyone used. It was expensive and quite often led to huge problems in lawns. That was in the days when Rodale had control of the organic gardening movement. Since the late 1990s, the use of grain meals has taken over with spectacular results and huge cost reductions. All the issues with compost are gone. Compost has uses, but fertilizing lawns is not one of them. In fact I dare say that the only reason there is an organic lawn care forum anywhere is due to the discovery that compost was a problem and ground grains was the solution. Generally all insects prefer the more natural use of grains rather than chemicals on the soil. In a 'normal,' healthy lawn, the beneficial insects will predominate. Why? Because 'healthy' is the definition of normal. When you have the bad bugs then something is out of balance. Something is not normal. Usually applying food of some sort will straighten things out. Sometimes grains are not the fastest answer. Sometimes molasses (a food) is a faster answer. If your ants are fire ants or another type of ant that is doing damage, the fastest solution is to give them a disease (organic!). The disease is called spinosa which causes all the insect's muscles to contract resulting in paralysis until death. The product is called spinosad or Conserve (trade name). There is a bait called Green Light Fire Ant Control with Conserve. Find a trail of fire ants and drop no more than a 3-finger pinch along the trail. I use a 2-finger pinch and have some left over. Fire ants will jump on it and start carrying it to the nest. The entire nest will collapse and die within 24 hours from just a few grains of the bait. Be careful how you use it, because it is very effective on many beneficial insects (bees and wasps come to mind). Try to target your pests. There is a similar product by Fertiloam, but I can't remember the name. Look for spinosad or Conserve. What organic matter? The organic matter that matters is the beneficial fungi in the soil. The population of fungi in soil far outweighs (literally) the population of all other microbes combined. Others are bacteria, protozoa, and micro arthropods (mini insects). You can have good fungi by watering regularly, the soap stuff from above, and feeding organic fertilizer. The occasional use of chemical fertilizer will not benefit your soil but may boost plant growth for a short time. The repeated and sustained use of nothing but chemicals WILL deplete the beneficial microbes in the soil and that can be a problem.