You should keep an eye on the sleeping environment's temperature and restrict the amount of light entering the space you sleep in. Eye masks are a cost-effective solution to reducing excessive light from entering your eyes. And more generally speaking, your level of comfort when you enter the bed is a good indicator of how well you can rest in that space (not too cold or hot, no blinking LEDs from devices, and so on.).
Try to avoid blue light and loud disturbances as much as possible before bedtime. There are multiple tools to reduce the amount of blue light emitted by screens, if you have the need to use a computer in the evening.
Overall health has a direct impact on your sleep. Remember to take proper care of your body -and mind- as this will result in better overall health. Eating "properly" (enough energy, nutrients and hydration, all in proper quantities) before bed will also improve your quality of sleep. Feeling bloated is a great way to stay awake for unnecessarily long periods of time.
Regular exercise is rewarding. Going to bed and falling asleep might be easier if you've exerted your body during the day.
The "Why these things -section":
 Humans react to stimuli. Constant arrhythmic sounds, especially loud ones, could keep someone awake, and their mind racing.
 "Bright light effects on body temperature, alertness, EEG and behavior"
P.Badia, B.Myers, M.Boecker, J.Culpepper, J.R.Harsh (Elsevier: Physiology & Behavior, Vol.50 Issue 3)
 Applies to nearly everything in life. Nominal systolic and diastolic pressures, no tightness in muscles, no grinding in joints is less to think about, and more time to focus on the task at hand.
 Being bloated can be uncomfortable, this can negatively affect your ability to relax and prepare for sleep.
 Moderation is key; however, the information available on the topic can be conflicted at times. People need to find what works for them, as age, and more broadly their own demographic, and type of exercise no doubt play a role.
Here is a general article on the topic from 2000: "Exercise and sleep" (Elsevier: Sleep Medicine Reviews, Vol.4 Issue 4) Helen S.Driver, Sheila R.Taylor.