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The first, you have to search any repositories that fulfill criteria of Utopian Guidelines.

The second, you ask the project owner if they mind to receive a new logo for their project.

The third, you show your logo proposal to them. Ask them to give any comments, suggestions, or revisions to your logo proposal.

If they like your logo, you can ask them to tell what size or type files they needed. Then, provide them all.

Send link of files or push directly on repository pull request. Another way is ask them to use your logo in their project as soon as possible.

I think its all what I usually do before I create any contribution. Hope this helpful for you @khaliloff :)

Thank you very much))