Am growing from seed and heard that when the third leaf starts to grow that it should be trimmed is this so? Have hunted for a good website on this but having no luck, Anyone have any advice on this?

Are you aware that all parts of this plant are poisonous.
There would be no reason to remove any leaves from this plant.
They are a succulent plant, don't overwater it and keep it out of the reach of pets and children.Wompoo.