To access store salesforce appointments, select your store from the portal page and log into Salesforce with the provided credentials. This will display a list of appointments that need updating, which can be edited directly from the list by selecting "edit". When editing an appointment, fields on the right like mobile number and connection type can be changed, and it's important to save after editing to remove the appointment from the list. The guide aims to make managing appointments on salesforce smoother and easier for stores.