To wish your Aquarius best friend a happy birthday, there are several creative ways you can do so in English. It's always good to make your wishes heartfelt and personalized to your friendship. Here are some suggestions to get you started:

1. Happy Birthday to my favorite Aquarian! May all your wishes come true today and every day.

2. Dear Aquarius friend, on your special day, I wish you all the happiness and love you deserve. Happy Birthday!

3. Here's to another year of outrageous adventures, hilarious mishaps, and unforgettable memories with my Aquarius BFF. Happy Birthday!

4. To my beautiful and eccentric water-bearer bestie, I hope your birthday is as unique and wonderful as you are. Cheers to another year of being fabulous!

5. Happy Birthday to the most independent and quirky person I know. You inspire me every day with your creativity, intelligence, and compassion. May your birthday be filled with joy and inspiration!

Beyond these basic wishes, you might want to add a personal touch to your birthday message. Consider what your friend likes and dislikes, their goals and dreams, and their quirks and qualities. Here are some ideas for more personalized messages:

- If your Aquarius friend is a social justice warrior, you might say: "On your birthday, I celebrate your passion and commitment to making the world a better place. May your voice continue to be heard and your actions continue to inspire change. Happy Birthday, dear friend!"

- If your Aquarius friend is a science buff, you might say: "Happy Birthday to my favorite innovator and explorer! May you continue to unlock the mysteries of the universe and push the boundaries of knowledge. Here's to a year of groundbreaking discoveries!"

- If your Aquarius friend is into astrology and spirituality, you might say: "Wishing my cosmic sister a very Happy Birthday! May the stars align to bring you peace, enlightenment, and cosmic blessings. Thank you for being a guiding light in my life."

- If your Aquarius friend is a foodie or a traveler, you might say: "Happy Birthday to my epicurean and globetrotting partner in crime! May your taste buds and wanderlust continue to lead you to new and amazing experiences. Keep exploring and savoring life!"

No matter how you choose to wish your Aquarius friend a happy birthday, remember to keep it sincere, thoughtful, and fun. Celebrate their unique qualities and remind them of how much they mean to you. Cheers to another year of friendship and adventure!