Key Learnings from Making Over 100 Deloitte Proposal Slide Decks

After spending countless hours crafting, refining, and sweating over more than 100 proposal slide decks during my time at Deloitte, I’ve developed some key insights that can help anyone in the corporate world, especially those working on high-stakes pitches. These aren’t just tips for making a slide pretty—these are the hard-won lessons that can turn a deck into a compelling, client-winning story. Whether you’re a consultant, project manager, or just the lucky one tasked with whipping up a pitch deck, these learnings should help you save time, energy, and a lot of frustration.

1. Start with the Story, Not the Slides

One of the biggest mistakes I’ve seen (and made) is jumping straight into PowerPoint. Your deck is not just a bunch of disconnected slides—it’s a story. Before you touch a slide, think about the narrative arc. What problem are you solving for the client? What’s the big idea? Why are you the best solution? What are the tangible results they can expect?

Tip: Start by sketching out the structure with pen and paper or in a document. Break it into three sections: the problem, your solution, and why your team is uniquely positioned to deliver results.

2. Structure is Everything

If your audience can’t follow the flow of your presentation, they’ll lose interest fast. There’s nothing worse than being halfway through a deck and realising the client still doesn’t understand what you’re offering because the deck’s all over the place.

A classic, foolproof structure is:

• The Problem: Define the client’s challenge (be precise).
• Your Solution: Highlight your approach, methodology, or product that addresses the challenge.
• Benefits: Show the clear, measurable outcomes (cost savings, efficiency gains, etc.).
• Credibility: Why your team or solution is the best for this job (relevant case studies, testimonials, etc.).
• Next Steps: What’s the client’s action plan? Make it clear and easy to follow.

3. The 10/20/30 Rule

This isn’t something Deloitte specifically invented, but it’s a golden rule I’ve found useful. Borrowed from Guy Kawasaki, it means:

• 10 slides maximum. Any more than that and you risk overwhelming the audience.
• 20 minutes to present it. People have short attention spans.
• 30-point font. This ensures you avoid cramming in too much information.

While proposal decks sometimes need to exceed these guidelines (especially on complex projects), keeping them in mind forces you to be succinct and clear.

4. Visuals Trump Text Every Time

Corporate decks often suffer from “text overload.” You’ve probably seen slides that are just walls of text. Nobody’s reading that in a live presentation. Visuals are far more impactful.

Use visuals to simplify complex ideas. Charts, graphs, process flows, and icons can quickly communicate your points without bogging the audience down in detail. Even something as simple as a well-designed timeline can make your proposal much easier to digest.

Pro tip: If your slide can’t be understood in 5 seconds, it’s too complex.

5. Customisation is Key

Clients can spot a template deck from a mile away. Even though Deloitte has some killer templates, I learned that a templated proposal, without tailoring, gets noticed for all the wrong reasons. Each slide needs to be customised to the client’s industry, needs, and specific problem.

This goes beyond swapping in the client’s logo—reference their strategy, mention recent news about their business, or show an understanding of their unique challenges. I once spent extra hours adding in details from the client’s latest shareholder report, and they appreciated the effort. That personal touch can make or break the deal.

6. Never Underestimate the Power of a Well-Written Executive Summary

The exec summary is often the only slide that some decision-makers will see. Make it count. This is where you succinctly capture the core message of the entire deck. It should stand alone, meaning if someone reads only that slide, they’ll still grasp the full proposal.

Focus on these points:

• What problem are you solving?
• What’s your approach or solution?
• What are the tangible benefits?
• What’s the investment and ROI?

Remember: Less is more. The executive summary should be concise, to the point, and devoid of jargon.

7. Data Drives Decisions

You can have the prettiest slide deck in the world, but without data, you’re relying on fluff. Hard data in the form of market research, case studies, benchmarks, and ROI projections is what will convince clients that your solution isn’t just a good idea—it’s a sound one.

At Deloitte, we often leveraged proprietary research or industry benchmarks to back up claims. Wherever possible, include numbers that quantify the potential impact your proposal will have on the client’s business. Think along the lines of:

• “This solution can save you 20% in operating costs annually.”
• “Similar clients have seen a 15% increase in productivity after implementation.”

8. The Rule of One

One of the more painful lessons I learned the hard way: one idea per slide. It’s tempting to cram multiple concepts into a single slide to save time, but that only creates confusion. Dedicate each slide to a single message or idea. This clarity makes your pitch easier to follow, and makes each slide a punchier, more impactful part of your story.

9. Iteration is Your Friend

No matter how perfect you think your first draft is, it’s not. Great decks are the result of continuous tweaking, reviewing, and refining. In the world of consulting, you’ll often get feedback from multiple stakeholders, and everyone has a different opinion. Don’t take it personally—iteration improves the final product.

That said, don’t over-iterate. At some point, you need to stop making tweaks and let the deck speak for itself.

10. Don’t Skimp on Design

We’re not all designers, but that doesn’t mean we shouldn’t respect the importance of good design. A well-designed deck is not just about looking pretty—it’s about making the information clear and engaging. At Deloitte, we often had design support, but when that wasn’t available, I’d keep things simple: consistent fonts, colours, and alignment go a long way. Avoid clutter and make sure there’s enough white space for everything to breathe.

A visually appealing slide deck can make a huge difference in how your proposal is received. Clean, professional design communicates that you’re serious and you’ve got your act together.

11. Know Your Audience

This might sound obvious, but tailoring your deck to your audience is essential. If you’re presenting to the C-suite, focus on high-level strategy and financial outcomes. If the audience is more operational, dive deeper into the technical aspects and execution.

I’ve made the mistake of going too deep into technical detail for an executive audience—they didn’t care about the how, just the results. Always ask yourself: Who’s in the room? What do they care about? And what’s going to make them say “yes”?

Conclusion: Proposal Decks are an Art and a Science

Creating proposal slide decks might seem like just another part of the job, but they’re actually one of the most powerful tools you have in winning business. When done right, a great deck not only tells a compelling story but also demonstrates your credibility, expertise, and understanding of the client’s needs.

After creating over 100 decks at Deloitte, I can confidently say that it’s as much about the thinking behind the slides as it is the design itself. Nail the narrative, keep things simple, and always focus on the client’s objectives. If you can do that, you’re well on your way to creating winning proposals.

And don’t forget—sometimes less really is more.