Organic grower Denise Dunne recommends this no-dig method for creating an instant herb garden on any piece of level ground, including a lawn. It is especially suitable for a tiny herb patch, a metre or two square. Mark out the site for the herb garden and cover it with a layer of newspaper, ten sheets thick. Overlap the edges so there are no gaps. If the weather is breezy, dampen the paper first. Outline the paper "garden" with an edging of bricks, logs, railway sleepers or whatever you fancy. If the paper is dry, hose it down to dampen and soften it. Cover with a layer of organic compost, 6 inches thick.
Plant herbs into the compost: in one metre-square, you can grow about a dozen plants. Water well. The newspaper weighed down by the compost will kill off the lawn and weeds underneath (persistent weeds, such as dandelion and bindweed, should probably be removed at the start, just to be sure). The paper eventually disintegrates and the herb-roots work their way into the soil below.