Regarding psychological treatment, which does not cure but makes the disease cope better, sleep hygiene, dynamic relaxation, cognitive behavioral therapy, and stretching are available.
Sleep hygiene: It consists of a part of cognitive-behavioral therapy by which certain stimuli must be linked to the action of sleeping, so that the response is as automatic as possible.
Whenever possible: the time to go to sleep should always be at the same time, without watching television or chatting until late hours, or staying up late on weekends; because the time to get up must also be the same every day of the week.
Electronic devices that emit bright blue light (mobile phones, tablets, computers) have the ability to activate neurons in the brain, which, if used late in the evening or at night and for a long time, can cause insomnia.
The bed should be used only for sleeping, not suitable for watching television or reading on it. The proper room temperature is between 20-22 degrees, night noises should be avoided. If the bed partner snores or the neighbors make noise, ear plugs can be used, if this does not work, the patient should move to another room. If light enters the room, a sleep mask can be used.
Try making the last thing you do before bedtime a relaxing activity, such as reading, listening to music, or doing relaxation practice. By doing that every night your body will know that bedtime is coming and will get ready for sleep.
Having a glass of warm milk is also a good remedy.
Avoid alcoholic beverages at night, exciting drinks (colas, tea, coffee, etc). Avoid smoking if you are not a regular smoker, if you are your body will need nicotine to avoid the deficiency syndrome that would come from not smoking and that would be worse, so smoke your last cigarette of the day.
Avoid tasks or conversations, discussions at the end of the day, that would load you with tension.
-- Sport: Going for a walk or swimming, or doing yoga have been shown to be sleep-promoting activities, provided they are done in moderation, without excessive fatigue and that their practice is before mid-afternoon. Swimming seems to be the most relaxing activity for the body.
-- Relaxation: there are many ways to practice relaxation: sitting like a monk, lying in bed or on a couch, but when you cannot keep your legs still it is difficult to practice relaxation, relaxation in a sitting or lying position should be left for when let us not have motor restlessness in the legs. But we can practice Relaxation Walking. (This technique will be explained in another post).
Gabapentin for Sleep?
Augmentation & No sleep
No sleep for a week 
Alternative treatments
Methadone treatment or not?
