Presentations and case studies?

Also, in general: don't try to introduce everything at once, you will encounter resistance.

Find one practice you feel it's going to improve the quality or cut down any expensive resource (time, manpower, etc.) and argue about its merits.

In my experience, the best way to convince somebody is by example. Salespeople now it! Reports, Statistics, White Papers are only helpful after the "customer" can see the benefit of the product/service you're selling.

So here's a suggestion. Spin up a docker instance of Jenkins or your preferred CI/CD and implement a build in it. Nothing fancy, but enough to show them how time can be saved. Contrast it with the current process. Speak their "language", tell them how the automation will give back more free time for other more important development and operations tasks. It will translate into money figures in their minds.

Make sure you understand their priorities and success criteria. That will allow you to identify what matters to them.
Find opportunities to talk to them about how DevOps practices can make their life easier or fulfill success criteria earlier.

Once you have their endorsement, propose a PoC to demonstrate concrete result.

This is directly copied from my Reddit posts from here: reddit.com/r/devops/comments/7tt2u.... Guys, when you copy something, give credits to the original author or creator. That is common sense.