写作时可以灵活运用一些形容词来描绘朋友的特点，同时也要注意语法和拼写的正确。
以下是一个如何写这个作文的示例：
My best friend is Lily. She has long brown hair and sparkling blue eyes. She is tall and always wears a cheerful smile on her face. I like her because she is kind-hearted, always ready to offer help whenever someone is in need. She is also a great listener and gives me valuable advice when I encounter difficulties.
Last summer, we had an unforgettable trip to the beach together. We laughed, played beach volleyball, and built sandcastles. It was so much fun. We even had a picnic under the shade of an umbrella and shared stories, dreams, and secrets. Spending time with Lily made me realize how lucky I am to have such an amazing friend. She is always there for me, through thick and thin, and brings so much joy and warmth into my life.
In conclusion, my friend Lily is not only beautiful on the outside, but also has a beautiful heart. I am truly grateful for her friendship and cherish every moment we spend together.