How can I make a second fork of a GitHub project?

I mean that I could just commit and push without making a pull request, but I want to do it the offical way and I want somebody else to review the changes before I push to a public project.

GitHub pull requests do not need to be submitted from a fork; they work within a single repository as well:

Pull requests are especially useful in the fork & pull model because they provide a way to notify project maintainers about changes in your fork. However, they're also useful in the shared repository model where they're used to initiate code review and general discussion about a set of changes before being merged into a mainline branch.

There's nothing stopping you from creating a pull request even if you don't technically have to. This is often considered a best practice, and GitHub's own Flow model is largely based on pull requests.

Creating a pull request within a single repository is very similar to creating one from a fork:

1. Create a feature branch and push your work to that branch on GitHub
2. In the GitHub web UI, switch to your feature branch
3. Click the "Compare" & review button

There is no way to have two forks of the same GitHub project unless you use two different GitHub accounts.

So:

1. Create a separate GitHub account (and verify the email)

2. Fork the project

3. Invite your main GitHub account as a "Collaborator" (from the settings)

You may need to add the extra step of creating an organization with the new GitHub account and inviting your main github account as an owner of the organization (also make sure your new fork is in that new organization). This will let you do things like deploy automatically to a Heroku app that is connected to your main GitHub account.

Why can't we just have multiple forks???