does any one know a simple and cost effective way to make my grass greener?

Fertilizer and water. If there is a better, more cost effective way than that, I'd be interested to know.

Get a soil test done, your local cooperative extension will do them for you, at a minimal cost. Follow their recommendations. Do realize that some types of grass have a lighter natural color than others. Bluegrass and certain types of fescue have a nice deep green color, so you may want to overseed with those varities. It would have helped to know where you are located, and what type of grass you have.

Spray with a liquid fish emulsion fertilizer.

Rake in some good compost and water thoroughly.

Water on a regular, adaquate schedule.

You could also try a homemade lawn tonic, a yahoo search will bring up several recipes. Personally I would eliminate the soap in most of them and add a couple teaspoons of epsom salts.

Any weed and feed type of product spread with a rolling spreader (NOT by hand...you'll burn the grass and kill it) and lots of water will make it green. Also, use lime pellets in acidy soil (around pine or other conifers) to help with the quality of your grass.

Spray paint.

Or pay someone to come and pollute the earth and tell you that you need to overwater your yard which washes the chemicals they just put on down the sewer so that they have to come back and do it all over again.

Just use an iron spray--it is cheeeep and will do the trick but it will also grow like a bad weed.

Yeah. Go stand on the other side of the fence ;)

Can of spray paint. Fast, cheap & easy!

The best way is to tell your dealer, but expect to pay more.

in my experience i like Scotts Turf Builder that is if you want to do it your self