If you are spreading seed over several hundred square feet (for example, re-seeding a lawn), you need a broadcast or drop seed spreader. But you can do many small-scale seeding tasks with a homemade seed spreader. A homemade seed spreader is appropriate for over-seeding a bare patch of lawn, or spreading wild flower mix evenly in a flower bed. You can make a seed spreader out of a recycled coffee can.
Acquire a used tin coffee can and two coffee can lids. You can use a 0.454kg can for smaller projects (for example, scattering mesclun lettuce seed), or a 1.36kg can for larger projects (over-seeding a bare patch of lawn).
Punch or drill 16 to 24 holes in the bottom of the coffee can. Use a drill or hammer and nail to punch the holes. The holes should be only slightly larger than the seed you are spreading. For grass seed, a 1/8-inch drill bit or size 4d nail should be sufficient.
Place the first lid over the bottom of the coffee can, and pour seed into the can. Seal the top of the coffee can with the second lid.
Remove the lid on the bottom of the coffee can and shake the can over the area you wish to seed.
If you are scattering wild flower seed or other small seed mixes (mesclun lettuce, etc), mix some sand in with your seed to get more even and wide-spaced distribution.