If they're big seeds, you could use a cell tray and sow one per cell to save pricking them out. If they're small, then try not to sow too many close together, as it's much more difficult when you have to separate them.

Sometimes it helps to mix small seeds with sand, to distribute them more easily. To separate later, I try for at least a couple of cm between seedlings. To thin out all except one or two seedlings in a 10 cm pot, I worry less about the spacing, and keep a pair of cuticle shears handy. The thinnings are great in salads!