Translating Custom Fields

I am lost on how to translate custom fields. I read the link on it, where it tells you to open in PoEdit, and import the latest .POT file, but I see no where to add fields to be translated. My form has:
Your name:*
Your email:
Your phone number:*

Which I need to be translated to 3 languages in addition to English. Again, I have tried PoEdit and the instructions, but those seem to pertain to existing form fields and the latest versions, how do I actually add a new field to the file and it’s translation? Thanks for any help.

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