I use granulated sugar and a salt shaker. A lot of the seeds I can see how they are distributed, and I shake around vertically, between sprinkles, etc. Fine sand would work too, just that it is heavier and seeds would want to stay on top plus they're a little harder to see how well mixed they are.

Thanks for your input. I think I had read about the sugar suggestion. Sure would be able to see the seeds better against the white sugar vs sand and like you said even fine sand would be heavier than sugar. Wonder if salt would work too?

No! Salt will kill your seedlings, you don't want salt even watered into your potting mix.