A little info about your project and/ or overview that explains what the project is about.
A short description of the motivation behind the creation and maintenance of the project. This should explain why the project exists.
Build status of continus integration i.e. travis, appveyor etc. Ex. -
If you're using any code style like xo, standard etc. That will help others while contributing to your project. Ex. -
Include logo/demo screenshot etc.
What makes your project stand out?
Show what the library does as concisely as possible, developers should be able to figure out how your project solves their problem by looking at the code example. Make sure the API you are showing off is obvious, and that your code is short and concise.
Provide step by step series of examples and explanations about how to get a development env running.
Depending on the size of the project, if it is small and simple enough the reference docs can be added to the README. For medium size to larger projects it is important to at least provide a link to where the API reference docs live.
Describe and show how to run the tests with code examples.
How to use?
If people like your project they’ll want to learn how they can use it. To do so include step by step guide to use your project.
Let people know how they can contribute into your project. A contributing guideline will be a big plus.
Give proper credits. This could be a link to any repo which inspired you to build this project, any blogposts or links to people who contrbuted in this project.
Anything else that seems useful
A short snippet describing the license (MIT, Apache etc)
MIT © Yourname