Like in other cases, the very first step is to create an application and obtain an access token in following steps:
- Create a Pinterest account or use an existing one.
- Go to https://developers.pinterest.com/.
- Go to Apps.
- Create a new app (you have to agree to the terms and conditions first).
- You will be redirected to the app management interface where you can find your access token.
- Save it for further use in your code.