Know the importance of love for the child. They need it. Don't feel awkward for being a parent to the autistic child. They are far more loving and creative.
Take your child everywhere. By getting them exposed to public places, you will not only get to know what delights them or makes them frantic, so as to understand more in depth about their unpredictable behaviour but also get acquainted with the society and its way of living.
Maintain a routine and be consistent with it. Ensure that they don't miss out therapies, and guidance sessions. They learn mostly from the therapy. Don't miss out on a chance to get their talent or abilities out. Most importantly, take out some time for them. Give them attention, they seek it badly.
Find out the different kinds of activities that can be fun. It will help in enhancing your child's behavior and learning; more than what education or therapy would do.
Be patient and stay positive. It will take a lot of time, but the improvement is not impossible. And, at the same time, ask people to accept your child, the way he is and make them understand what your child is actually going through.