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How about cutting loose from reason for once in a while?
Literal
Once-in-a-while reason [gen-の] hoops [obj-を] remove-[try-てみませんか].
たまには 'occasionally / once in a while' with the contrastive には — suggesting 'this particular occasion' against usual behavior. 理性のタガを外す literally 'remove the hoops of reason' — a vivid idiom using タガ (the wooden hoops holding a barrel together): if the hoops come off, the barrel falls apart. It means 'to let loose / throw off restraint / abandon caution.' ~てみませんか 'won't you try X?' is the polite negative-question invitation.