Don't need to - they will germinate just on the soil surface. I usually rough up the soil some then sow in place, pressing down lightly to make a good contact and prevent any seed from blowing away.

they reseed rather freely .. hence they dont bury themselves ...

on the other hand.. if i were doing it ... i would rake the soil loose.. just a quarter inch or so ... and put the seed down.. then tamp the soil down with my boot ... soil contact is good ... maybe even do a couple in a small pot.. and try transplanting them when they are an inch or 2 big ... perhaps on a rainy day ...

if you have a lot of seed .... do it both ways.. and report back ...

ken