Below are some tips from the book "What Do I Do When my Child Loses control by Polly Greenberg. The book seems to be written for parents with typically developing children who are between the ages of 3-7. She calls the ideas outlined below "Tantrum Tamers." They aren't meant to address sensory or anxiety overload, but I believe that some of these ideas may work or be adapted for the child with autism--even those who are older than seven since many children with ASD are running a few years behind developmentally.
"Here are some ideas that work for many parents. If your child won't go to an out of the way time out place:
1. Use reverse time out.
Walk out yourself. Shut yourself in a room where you have a good magazine to read, and enjoy it. keep one there, just in case. If necessary, take the baby, but it's better to leave your other children out of this, if possible.) After the storm has subsided and blue skies appear again, say nothing about the wild behavior. Move on in a friendly way.
My input: I like the idea of the reverse time out, but if the child is older and able to understand, it might be a good idea to actually talk about the wild behavior after the child has calmed down. Try to make sure you and your child have an idea of what caused the meltdown. (Writing down the factors surrounding a meltdown afterward may give you some insight.) While offering some reassurance, try to help your child understand why that behavior was unacceptable. This may help cut down on the probability that a tantrum or meltdown will happen over the exact same or during similar circumstances in the future.
2. Start time out after the tantrum has wound down.
Say, "You'll start your time out when your enough in control of yourself to go into your room." Later, say, " I see you've gotten yourself calm. Good. Now spend some time alone (as many minutes as equal the child's age), and figure out what to do next time you feel frustrated instead of having a fit. I'll give you the timer. Come back in x minutes if you feel ready."
My input: This is a really good idea because it might be hard for a child with ASD to stay in anyone place while melting down.
3. If this causes junior to renew his tantrum, go through the same procedures again.
Don't discuss anything with your child. Don't reward this unacceptable behavior with your attention. (is there anything a child considers more rewarding?) state what is now going to happen and make it happen.
My input: During the meltdown or tantrum, sometimes it's impossible to get a word in edgewise. I suggest trying to remain calm and doing one's best to make sure the child is safe (a reverse time out may not work, if a child is a danger to himself.)
4. Give a choice: time out of the loss of something he likes.
(The video he usually gets to watch one afternoon a week? the pack of sugar-free gum he gets on Saturdays?) If your child weighs almost as much as you do, or you have a bad back or some such, say, "You can go to time out right now or you can skip the video, your choice."
My input: This might work after the child has calmed down and can understand choices, which are often difficult for children with ASD to make--especially younger children.
Note: The book is only 48 pages long and is easy to read. However, it was published in 1997 by Scholastic Books and seems to be out of print. It only seems to be available on Ebay with a January 15, 2009 deadline for purchasing ($1, plus $4 for U.S. shipping).