It's wise to save money for emergencies.

Literal

By-chance's case [for-に備えて] money [object-を] save do thing [topic-は] wise [copula-だ].

ためる ('to accumulate, to save up') is the everyday verb for stockpiling — money, points, water in a tub. The お before 金 is the honorific prefix; words for money, food, and bath universally take お in modern speech, having essentially lexicalized the prefix as part of the standard form. 万一に備えて ('in preparation for the unlikely') is a set phrase commonly seen in financial-advice and emergency-preparedness contexts.