number one: good nights of sleep.
nothing works to relax me if I didn't sleep well. it is a must.
it's pointless to try anything else if you're not sleeping well.
then, number two, the thing that makes me sleep well: amitriptyline.
(could be mirtazapine as well. both of them are great for me)
plus my practices of sleep hygiene, which are many and go beyond the scope of this post.