What is the best design pattern for RESTfull Api Design

This week I finally started with learning developing API´s.

At this moment my API is able to do simple get, post, put and delete request and return information from the database as a JSON string.

I build my current API with Slim 3, a lightweight PHP framework.

For now, I search for good blogs, articles and so on about API developing and API design.

Thank for posting interesting things.