Attaining good "sleep hygiene" has been a huge goal for me for a while now. For me, personally, I had to rewire my brain to recognise my bedroom as a place of sleep and rest - so that means I try not to use my phone, or computer or read study notes when I am in bed, or if possible, my bedroom. When I commit to this rule (I sometimes fall off the bandwagon), my sleep is amazing !!
However, there are some great tips in this thread that I will definitely try to adopt.