Autism from a mama who has been there. I am going to try to post every day this month. Please feel free to ask questions in the comments.
Before our autistic son became verbal, sound effects were a more effective way to communicate with him than actual words. I am terrible with sound effects, but he understood Erch, Vroom, and Honk.
A harness was an absolute necessity. I can't tell you how many times that harness saved his life. Because kids with autism look normal, don't expect to get help, sympathy, or understanding from strangers. Instead, expect snickers, eye rolls, and whispers. Get over it. GET OVER IT. I mean it. GET. OVER IT. It's life, and your child's safety is more important than what anybody thinks of you.
Earplugs, in the beginning, he hated any kind of earmuff, headphone, any over the head ear protection-- but he tolerated silicone, shape-able earplugs. He could take them out and put them in a box in his pocket, and he could put them back in whenever he needed them. But noise-canceling headphones have come a long way in the last 25 years. Explore the options and find out what works best for your child.
Sunglasses are essential. Wrap-around sunglasses are the best. But you will have to find a pair that your child is willing to wear. They can't be too tight or too loose. You might try on 10 to 15 pairs before you find the one that your child will tolerate. And they're necessary, for not just the outdoors, but also in places with high illumination: gymnasiums, cafeterias, stores, doctor's offices, etc. Other difficult areas are places with mirrors and other reflective surfaces: lobbies, department store bathrooms, gymnasiums, pools, courthouses, office buildings, etc. (Your child sees EVERY reflection, and it IS overwhelming. This is a possible reason why eye contact is so difficult, your eyes are reflective.)
Writing tools. You can save yourself some time and lay out all the options in front of your child and see what he/ she chooses on his/ her own. They may not be able to tell you why they've determined to use that particular item, but at least you'll know that there is something they're willing to use. Our son would only use round pencils until we found triangle-shaped spongy grips that could slide over any pencil. He would only use colored pencils, never crayons. (I once bought a box of colored pencils for every student in his class because his teacher insisted that they all use the same thing, and I knew he could not use crayons.) Later, he told us it was because crayons smell. I had no idea.
There are fantastic options today for our autistic children, ranging from the nonverbal to those with additional medical problems that have a writing or speaking difficulty. It is incredible how far technology has come to meet the needs of our children.
Audible books are wonderful. It is difficult for the autistic child to focus on a white page with black print for long periods, and audible books are so helpful. You can find most assigned reading in audible book form. If this is a particular problem for your child, you can even request that the school supply audible versions of textbooks.
We know that our children have heightened senses. But we also know we must teach them to function in the world. So part of that is teaching them to overcome disgusting things. Washing dishes by hand, taking out the garbage, picking up dog poop, all of the elements of healthy everyday life. Using rubber gloves, nose plugs, or face masks can help your child transition during this challenging learning process.
Every child is different, and you know your child best, so pay close attention to reactions and make a note of what works.
Remember to celebrate the small stuff. Be flexible. Laugh.