For this example, we will see two things: 1) The customization of the admin panel itself, by updating the content of the `/admin/` home page; 2) We will see how to update the interface of a plugin, by replacing the `date` format in the content manager list view.
First, you will have to read the [customization concept](../concepts/customization.md), it will help you understand how to customize all of your application.
If you are following the customization concept, you can already create a `./admin` folder in your application.
### Target the file to update
Then you will have to investigate into the [`strapi-admin`](https://github.com/strapi/strapi/tree/master/packages/strapi-admin) package to find the file that is used to display the admin panel home page.
Here is the [HomePage container](https://github.com/strapi/strapi/tree/master/packages/strapi-admin/admin/src/containers/HomePage/index.js) you will have to update.
In this new file, paste the current [HomePage container](https://github.com/strapi/strapi/tree/master/packages/strapi-admin/admin/src/containers/HomePage/index.js) code.
Then you will have to investigate into the [`strapi-plugin-content-manager`](https://github.com/strapi/strapi/tree/master/packages/strapi-plugin-content-manager) package to find the file that is used to format the date for the list view.
Here is the [Row component](https://github.com/strapi/strapi/blob/master/packages/strapi-plugin-content-manager/admin/src/components/CustomTable/Row.js) which requires a [dedicated file](https://github.com/strapi/strapi/blob/master/packages/strapi-plugin-content-manager/admin/src/utils/dateFormats.js) to modify the date display.
In this new file, paste the current [dateFormats](https://github.com/strapi/strapi/blob/master/packages/strapi-plugin-content-manager/admin/src/utils/dateFormats.js) code.
And tada, the date will now display with the new format.
## Build the new admin
Well now you have the admin panel you want. But during all the process, the admin panel was updated on the run time because of the command `yarn develop --watch-admin`.
If you start your application using `yarn start` or `yarn develop` the admin will be the old version. Your updates are not applied.
To do so, you have to build the admin panel using the following command `yarn build`.