Technical Writer | How do I prove 3 Years work experience?

Does anyone know what do kind of documentation I need to prove 3 years work experience?

Do I need a letter from previous employers?

What information should be on the letter?

Do I need pay stubs?

Does all my work experience have to be as a technical writer?

Any other advice for someone who's applying for TN status as a Technical Writer with a Diploma + 3 years work experience?

Thanks!

You don't need letters from prior employers but you should. You can have the letters notarized for maximum effect.

The letter should indicate the period of employment and your duties and responsibilities and the author should indicate their relationship to you as a former employee.

The three years should be in technical writing or a related field.

Does it matter who writes the letter?

Can my boss, secretary, etc write the letter or does it have to come from the HR department?

Thanks for all the help!

Anyone who can attest to your work.