Summarize:

These are small "v" shaped lines in your seedbed, which you can use to separate seedlings. Using drills allows you to recognize the plants amidst weeds and other plants. Seeds need moist soil to germinate. Plant them according to the seed package directions for starting seeds. This will keep your seedbed from overcrowding before you transplant. Compost the unwanted seedlings.
Create "drills" in the soil with a hoe. Water along the length of the seedbed. Sprinkle seedlings just barely into the soil along the drill/row. Thin the seedlings after they germinate and start to grow.