Lots of vegetables have very tiny seeds. You can buy a variety of contraptions to help control how many seeds you put down in the soil, but the easiest planting I have done was with lettuce paper seed tape last year. I bought it from a commercial seed vendor online and it made planting those tiny seeds a cakewalk. I had a small length of it left over this year, but only a fraction of what I want to plant in total, and it occurred to me that making seed tape would be pretty much the easiest thing in the world and it would help the planting go more smoothly. Here is how I did it.
Step 1: What you'll need
Toilet paper - thinner is better; I used Scott
Spritzer filled with water
Step 2: Cut strips
Cut toilet paper lengthwise and fold halves lengthwise.
Step 3: Add seeds to strips
Open each half back up a bit. Add seeds, spacing them out as recommended in planting instructions. In my case, I copied the spacing from the commercial seed tape I had left over. Then fold the top half back down carefully.
Step 4: Spritz and spritz some more
Spritz water over the strips. Begin very gently, with a fine mist, until the top of each strip is somewhat wetted and weighed down. Then saturate the strips thoroughly. With your fingers, pat them down so that top and bottom are totally stuck together with the water.
Step 5: Wait...
Wait until the strips are fairly dry. As the strips get mostly dry you might see places where they aren't stuck together completely, so re-wet those places and press them down so they stay stuck.
Step 6: Plant!
Plant! Draw a spade or a stick in a line in the dirt to create a trough, lay the tape down along the bottom of the trough, and cover with dirt. You'll need to check the planting instructions for how deep your seeds should be planted. Mine are lettuce seeds, so I put about a cm of soil on top.