If you want to grow your own lettuce or carrots, you'll have a hard time trying to plant the tiny seeds by hand. Instead, you can plant a biodegradable tape with the seeds embedded into it. All you need to make your own is some newspaper, some flour and the seeds you want to plant.
Crafting blog Giver's Log recommends using one-quarter cup of flour and just enough water to make a paste. Cut out long strips of newspaper, paper bags or toilet paper. Brush a bit of paste onto the paper and add your seeds, making sure they're spaced out correctly. Wait for the paste to dry completely, and then roll up your tape.
When you're ready to use the tape, all you need to do is lay it down on top of the soil, water it, and then place a bit of loose soil on top.
DIY Seed Tape [Giver's Log]