This document introduces a new guide called "Investing in Energy" that provides a framework to help prepare and present successful energy investment proposals. The guide outlines a five-stage process: 1) gather necessary information, 2) assess proposals realistically, 3) develop an influence strategy, 4) present proposals to win support, and 5) follow through. It also explains basic financial appraisal techniques to assess proposals. The goal is to help present energy-saving investments in a way that addresses stakeholders' priorities and shows clear economic benefits and strategic value.