I will break down it in two parts : Outcome & Investment  
  
 Outcome - Quantify the revenue impact, impact on customers, upselling opportunities  
  
 Investments - Break down the investments in smaller chunks, give a milestone checker

These work in most business raw ideas! Gold advice 🌟

Consultant

Product Manager

The way you do it is with clear metrics around success and failure.
Leaders are capital allocators and critical thinkers.

The way you put ideas forth is by showing the risk, the reward and the learning(/value-add)

If the trifecta works then ideas are approved but I agree with @ElonMast and @DualWannabe here.

It is deep research as well as executing as much as you can for an MVP. Look and feel is very important because it feels tangible and real.

Very simply put execute shit over the weekend if you are FE/Design, or figure out an iterative roll out that minimizes risk for stakeholders.

Then it is all about executing fast. Come up with an MVP and sell it internally. Less hands the better to solve Principal Agent Problem.

Share your idea if you're comfortable and I'll help in whatever way I can. I've worked primarily on moonshot projects and with VCs so maybe some of it might be helpful

Product Marketing Manager

Don’t waste dev bandwidth and develop a MVP by your own. GPT and other resources has made ideating 10x easier than before.  
  
 Crunch your weekend over this, release as a private beta and then show the impact by quantifying the adoption.

Break that idea in a few parts: Problem Statement, Goal, Solution, User Journey, Input Metric and Output Metric. 
 Considering it's a moonshot, just cross-check with your Tech if it can even be done. Take a ball-park estimate for Cost Estimation if it can be done.

Every startup founder targeting a revolutionary change targeting a large TAM would be similar to an employee within the org pitching for a moonshot idea - with the difference being that founder pitches to investors and makes a case for the venture and here you are pitching internal company leadership for capital allocation. Frameworks for thinking and pitching remain more or less the same. But the major difference comes in risk appetite. An investor hedges the risk by investing in many moonshots but every company's risk appetite may be different based on stage of the company and it's priorities. Some companies like Google encourage moonshot thinking due to sheer nature of their scale and need for constant innovation.. whereas some midsize company fighting to survive or barely making profits would be very risk averse. So before pitching a moonshot, you need to think about how your company thinks about innovation and how much is their appetite to take large risky bets. And if there is an appetite then you need to think like an entrepreneur making a business case to your management for capital allocation.

Director Product

I see a lot of answers mentioning the standard data-impact framework but if I am not mistaken moon shots by their very definition, are ideas that do not have short-term guarantees of metric movement, high outcome volatility and low likelihoods of success. Such ideas can’t be identified those standard revenue/cost impact frameworks. To pitch a moonshot idea, you need to concretely establish that the problem it solves for actually exists, and other standard ideas out there underserve the problem. Once you can convince leadership about the existence of and the need to solve said problem, pitching your idea is then about building a case and iterating it on the smallest successful scale (mvp) and then you can build your revenue/cost impact case around it.

Lawyer

Title.   How do you build the comfort and confidence to double down on an idea that might work but sounds like a real hail mary shot?

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Title. 

How do you build the comfort and confidence to double down on an idea that might work but sounds like a real hail mary shot?

How do you sell moonshot ideas to Leadership?