Use your cell phone to set task reminders that will vibrate or beep for couple of times and stop automatically. Set the first reminder to go off after 20 mins since you start your WILD and the next one at 35 mins. However, you have to practice to wake up and not move a bit to the task reminders. If you can wake up and not move, use task reminders. Uou don't need to have an anchor to keep you awake during WILD.