You can find example SDK application in the github repository

This application is hosted on example.rarible.org

Example applications demonstrates how to:

yarn install --ignore-engines && yarn bootstrap && yarn build-all

cd packages/example
yarn start

The application is available at http://localhost:3000

Usually example app page consists of a simple form for executing action and example code which can help you use.

This is how page about selling NFT token looks like:

Rarible Protocol SDK Example application can be a great source of information how to use SDK