You can cover them with soil 1x to 2x the width of the seed. 1/2 inch should be fine. I also like to throw some "light mulch" on top to retain moisture, such as shredded leaves or pine needles, just covering so that you can't see the soil surface.
"That land is a community is the basic concept of ecology, but that land is to be loved and respected is an extension of ethics." — Aldo Leopold
