Advice for Sichaun jiuzhaogou park and Huanglong

We are a family of 3 adults and will arrive in JZG and stay in Sheratopn hotel for 3 nights in mid September. We would like to visit the Park and make a day trip to Huanglong. Please advise what is the best way to go about. Is there an online booking of the entracne ticket to avoid the long queue. Thanks for any advice.

Violette Tan of Malaysia.