1. Fertilize at least 3 times a year, preferably 5 times.
You can see significant gains in greenness when you fertilize more than 2 times a year. I used to be one of those Spring/Fall guys until I found out my error. I couldn't believe the results I got just by adding in one more fertilizer application.
2. Fertilize no less than 2 months apart.
While fertilizing more sounds good, too much isn't a good thing. Try to spread your applications out to at least every 2 months. Just divide the number of active growing months by the number of applications you intend to apply and you have the number to use to equally spread out your fertilizer application dates.
3. Mix in specialty fertilizers to address other lawn issues.
There are all kinds of specialty fertilizers out there like weed & feed, insect killer, and winterizers. You can save some time and money by addressing two issues at once if you have them.
4. Get a high quality spreader to help spread equally over the lawn.
It is so important that you don't get too much fertilizer in one area and that the fertilizer gets spread evenly across the lawn. You really want to avoid fertilizer burn because it is counter intuitive to your goals of a green lawn.
5. Make sure to water the grass after your done.
Don't forget to water in the fertilizer after your done. This helps get the fertilizer in the soil where it needs to be so your grass can take advantage of it.
Do these five tips this year and your lawn will see significant gains in density and color. Also, you will have far less trouble with weeds, disease, and other lawn problems because your grass will be healthier.