This is the seed pod that will grow on the very top of a mature basil plant

Cut it, at the very spot where the sepals (small leaves at the bottom) stop growing

These are the 4 seed pods that I had gotten from that same plant

Carefully search the pods and remove the seeds without injuring them

Leave the seeds to dry for 1 week. Then they will be ready to plant.

I hope this guide has helped. Please comment or follow me. Thanks.