I use duration maps a lot in therapy. Duration maps provide a visual representation for children so they know how much time is left before they can be (or have to) be done with an activity. A simple way to do one would be if your child has 5 minutes left in activity to draw 5 circles on a piece of paper. Let your child know that your have 5 minutes left to complete the activity. For some children, it's helpful to have a visual representation of what is next on the schedule to make the transition easier.
I use duration maps a lot to help my clients know how many trials or repetitions they need to complete before they will be finished. Sometimes I just hold up my fingers, sometimes I draw out circles on a piece of paper. Today I wanted to draw a map but realized I didn't have a piece of paper nearby. Oddly enough, I did have a paper plate handy.
Then we finished up our activity. Every time we finished a 3 picture cards, we got to "eat" a cookie. We crossed off the cookie and made obnoxious cookie eating noises.
My drawings were horrible (clearly) but it was a really fun and motivating activity for the client I worked with.