Originally Posted by Taf

Moss grows on compacted, poorly drained soil, and often in shady areas too, so push fork tines in a few inches then lean back on the handle to open up the soil. Do this every few inches in the mossy area. Lawn sand helps too. It usually contains iron which moss hates. Don't walk on it for a while though or you'll bring rusty stains into the house. The moss will blacken as it dies, then you just use a lawn rake to clear it (and give yourself a good cardiac workout too ).

Don't cut the grass too short either!