Sedum has tiny seeds which should be mixed with fine sand for an even sowing. Sow Sedum ground cover seeds indoors 6 - 8 weeks before the last frost is expected. Use small pots or flats and a sterile starter mix.
Pre-moisten the starter mix and sow Sedum seeds on the surface. Press the seed into the moistened soil, and do not cover it. Keep the seeds moist but not saturated until they germinate. Water from the underside of the pots or use a spray bottle and lightly mist the seeds.