how to raise a child without gender bias?

The points that Ling and Racheal shared are really good - basically, it's just trying to raise them without the discrimination against anything labelled for specific genders. This includes (but definitely not limited to) colours of the items your child uses/wears, cartoons/characters your child likes or watches, toys that your child plays with, hobbies/interests that your child has ... and in the future, the desire of wanting to identify as something your child wasn't born with! The simplest way you can do this is just to respect what your child likes - blue/pink, ballet/taekwondo, princesses/cars, race cars/dolls - give your child the freedom and support to do what they like :)