I find that sleepless nights tend to go in cycles and can become self perpetuating.
Can't sleep at night so you tend to nap during the day and become convinced each night that you won't sleep ...... so you don't.
Lay off the caffeine loaded drinks after 5pm, eat sensibly earlier in the day rather than mid to late evening, stop worrying about not being able to sleep and do not watch TV after 10pm. I do find that relaxing music in the bedroom can help but it can sometimes have the opposite effect because I am enjoying listening to it. Actually Horlicks or similar at bedtime does help.