[xupybd]

She picks up my errors and laughs as English is her second language and my first. She has also noted that I use commas in strange places and don't use them when I should. My writing also contains too much repetition. For example I often will start several sentences the same way in a paragraph.

I should note, that the laughter is not discouraging, it's simply the way we interact.

[ppppwwwww]

The reason for asking was that I expect she knows you best, and she might give the most direct and tangible advice on what to improve.

I'd work on these aspects first, then move on to some suggestions in this thread.

Something that has worked for me is to keep a list of mistakes I made in the past, or improvements suggested to me. I use it as a form of checklist to go through before sending off a new document, to at least avoid mistakes I've made in the past.