How to get better sleep at night ?

Probably diet: At age 23 you should have no problem with sleep. Your brain is dependent on a pristine diet so get rid of the "junk" food and beverages, particularly the sweet sugary stuff, even diet drinks.

Tips: Limit daytime naps, limit activities in bed to sleep and sex, create a regular bedtime schedule, keep the room dark and quiet, avoid alcohol/nicotine, no caffeine after 2pm, exercise earlier in the day, de-stress, keep the room temperature a little cool, for some white noise machines may help and get comfortable. If those don't help sometimes sleepytime tea, warm milk or melatonin can be beneficial.