Autism and behavior charts
These can be very effective is utilized in a way that makes them a motivator for the child. Letting them visually see the chart and allowing them to put the marks on it for whatever behavior you are trying to modify can be helpful as well.
Knowing how much to use a behavior chart is very important as well. Some children will do well with a daily amount of marks or stars they are working towards as a goal. Others will need much more intense use of the chart, maybe even as much as hourly or less.
The point is to modify the behavior in a way that the child is in charge of. It helps them see the results of using their tools (whatever therapy suggests) to be productive at home or in class. Because autistic children struggle with things that are not black and white to them this system makes for an easy visual reminder.