Hey Karrena,
If you want me to be specific for the field you created, let me know the field and table you added it to.
For my example I will add a new field to Contacts table: "Age"
Now in the CRM_CustomerList screen, I will customize the screen and add the field to the Grid.
First let's Edit the Grid:
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Head over to Step 2 of 9: Add the new Field as a Column
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Now after a Save & Close/Publish if you go back to the screen (in our example CustomerList) that field will be available in the Grid.
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If you're new to Method customization I would recommend watching a few webinars here to get you started. Some good ones for you would be the Intro to Customization then Intro to Actions.
-- Mortaza