To cast a basic protective spell, a young wizard needs to be calm and focused. They should imagine a strong, invisible shield surrounding them, made of a magical force. The wizard then says the incantation, 'Aegis Protego,' while making a circular motion with their wand. The combination of mental focus, wand movement, and spoken words will create a barrier that can help protect them from minor threats.
Imagine you are an expert in the field of magic and wizardry from a fantasy world. Explain in simple terms how someone could cast a basic protective spell.