In the event that you perchance upon a mythological entity, and said entity or, dare I say, entities, have desired coconuts, the directions for capturing said coconuts is as follows:
Step 1: Determine if entity — say, your brother — is malicious in intent, or simply a selfish flesh-eating neanderthal.
Step 2: Break his ankles, or perhaps if you feel lucky, both pinky toes.
Step 3: Steal said coconut, bash open with rock and/or machete.
This of course can only work in aforementioned mythical kingdoms. If your brother is Pelops, and you are Tantalus, then you are fully fucked. Perhaps...