I found 2 ways to add Donate function in your github project.

• Markdown
• Button

You can get link of image file in SVG file format like this from http://shields.io/ and concatinate it with your email code in your PayPal account, please see example below:

The button in Donation like Markdown topic but only change the image.

Methods :

• Buy me a coffee
• Ko-fi

If this project help you reduce time to develop, you can give me a cup of coffee :)