Growing from a seed
Lemongrass is a very easy herb to grow from seeds. The only problem you need to be aware of when planting is that the seeds are very small, fine and have a dandelion seed shape to them making them VERY easy for the wind to pick up. Plant the seeds in a seedling pot using seed raising mix. The seeds, should germinate within a week and you will see some thin lemon-coloured shoots poking out of the soil. As the seedling shoots grow (very slowly I may add), they turn from a lemoney-yellow to a rose pink. This makes them a bit more fun than your usual green, two-leaf seedling.
Find a spot that gets some sun; I choose afternoon sun as it is a bit more gentle on the seeds than the morning sun. Then make sure you water the seeds/seedlings once a day. You will only need a few drops of water to wet the soil as you do not want to drown the baby lemongrass.