How to cultivate Equanimity?

*Question is grammatically similar to this question but different in content.* Apparently, Equanimity is not indifference but a feeling in itself. According to the Note at the bottom of Potaliya Sutta. ; > MN 137 (passage § 179 in The Wings to Awakening) identifies **"equanimity based on multiplicity" as equanimity with regard to forms, sounds, smells, tastes, and tactile sensations**. It identifies "equanimity based on singleness" as the four formless attainments. In the context of this sutta, however, the Commentary defines **equanimity based on singleness as the fourth jhana**, and this interpretation seems correct. Toward the end of this passage, the equanimity based on singleness functions as the basis for the three knowledges, a function that is normally filled by the fourth jhana. As I understand, there is Equanimity with regards to sense bases and one generated through Jhnana. My question is, **How to Cultivate this Equanimity wrt multiplicity? Will the one wrt Jhnana get cultivated by itself**? The Indriya-Bhavana sutta mentions it as **peaceful and exquisite**, does developing that feeling in face of changing circumstances account to equanimity?