Beyond using the latest version of the Collection Navigation and Shopping Cart widgets, the storefront does not have to do anything else to ensure that the correct catalog and price group is shown to a logged in shopper. Server side code determines which catalog and price group to show and passes it to the storefront. The storefront then displays the catalog and price group it has been passed, via these two widgets. See the Create page layouts for account-based storefronts section for detailed instructions on making sure you are using the latest versions.