How do I add my email subscriber list

I've tried everything. I have reformatted my list in text and csv - nothing is working. I have a list of over 3500 people and I can't get it to import.

Are there specific examples of how a list should be formatted? This is the second time I've asked this question.

PLEASE - I'm not a programmer and I signed up primarily to use this e-newsletter (I cancelled my a weber) - I'm paying monthly.

Please help me.

Thanks,

Jaie