Step-By-Step Guide:

1. Select Settings > Merge Fields in the administrator toolbar
   
   
2. The merge field list will open in a new window
   
   
3. You can find a merge field in the Search tab, the # is not required
   
   
4. To edit, select the white arrow next to the merge field
   
   
5. Type in the new value and save changes
   
   
6. Refresh the browser and the change will have updated throughout the site

Video Guide:

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