In order to be ready to sleep at bedtime you need to proactively prepare your body and mind. You can do this by designing a pre-sleep routine.
Work backwards from your chosen sleep time identifying the tasks that best prepare you for sleep and the times at which these should feature. For example:
You can continue this exercise through your work day and even into the early morning. The more guidance you give yourself throughout your day, the more likely you’ll be to make positive choices that result in great sleep.