Thread: Take it down a notch

Does anyone have a good translation for that? Like"Dima is too angry at work, if he learns to just take it down a notch it'll help him a great deal."

Almost literal translation "понизить/снизить планку" is used in Russian in context of level of expectations/requirements. For example "Лена мечтала выйти замуж за Принца на белом коне, но ей пришлось снизить планку.".
In context of actions which have some kind of speed or motion characteristics there is idiom "сбавить обороты" (to lower rates). For example "Дима слишком много работает. Ему надо сбавить обороты.".
In context of anger state there is idiom "выпустить пар" (to let steam go out ("chill out" idiom in English)). However "выпустить пар" is different from "остыть" ("chill out" literally) because it doesn't imply for process to be calm ("calm down" - "успокоится"). "Выпустить пар" can be redirection of anger, possibly (but not mandatory) in safe manner.