<aside> <img src="https://img.icons8.com/ios/250/000000/info.png" alt="https://img.icons8.com/ios/250/000000/info.png" width="40px" /> Create a sponsorship page that you can share with potential sponsors, advertisers and brand deals. It's always more professional & efficient to have all your information in one place that you can point interested parties to.
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Here's a list of potential sponsors for your youtube channel. Large companies have partnership application pages. It's also entirely possible to get sponsorship from smaller companies if you can pitch your channel effectively to them.
Here are some pretty media kit templates. In my history of negotiating for brand deals and sponsorships, I noticed that good design goes a long way so do spend some time making it look good.
Media Kit Presentation Templates from GraphicRiver
It should be between 7-13 pages, no more. These people are busy!