Close the running instance of the appium (if any) opened in terminal and start appium UI by clicking on Start Server.
Once server starts you will see a new screen as shown below:
Click on Start Inspector Session as shown below:
A new screen will come up. Make sure ‘Automatic server’ is selected on the top header tab.
Add specific capabilities in desired capabilities one by one and save it with a suitable name. 1st field text-box, enter key name 2nd field is drop down, select appropriate option [text, Boolean, file path etc] 3rd field is text-box, enter the value for respective key.
Go to saved capabilities tab and click on the name of the capability you just created above.
Click on Start Session to see the inspector window [make sure your application is present on the mobile device connected to machine]
Appium inspector window will come up and you can find your locators using this window