I’ll try to provide a literal translation.
Although Fähigkeit can be translated as skill, it’s rather an ability.
Fertigkeit is a skill.
is used for solid objects or metaphorically for beloved ones.
could be misinterpreted as to receive, especially when used together with Fähigkeit.
is unambiguous when used with Fertigkeit.
plays in the same league (it’s one of its synonyms) while shorter, therefore
eine Fertigkeit wahren
For “emotional skills”, like humor (mentioned in the comments), use Wesensart instead. Additionally I think Matthias’ in Übung bleiben" is a very good choice. It covers all grounds and is more colloquial.