편한 대로 == (부르기에) 편한 대로 => as is convenient for you / whatever is convenient for you 편하다 means both "comfortable" and "convenient". ~(ㄴ/은/는) 대로 is like "as", meaning "the same way as ...". It can also mean "as soon as (something happens)". Examples: - 여태까지 해 오던 대로 하자: Let's do it the way we've been doing so far. - 선생님이 시키는 대로 하거라: Do as your teacher tells you. - 형편이 좋아지는 대로 이사할 것이다: We'll move as soon as things get better. As for what to call them, calling someone by their name without the title can sound very rude, so it's a bad idea. If she belongs to an organization and you know her official title, last name with the title is the best, as in 박 대리님. Alternatively, if they are running a website, you may call them 운영자 님(manager, owner) or 관리자 님 (administrator). These informal titles are usually said without the person's name. You may however include the site name, like "NAME 운영자 님", especially in the beginning of the correspondence.

I'm not native korean, I still learn too. but I will sharing from what the article that I read. You can call their name like "나연-씨" becomes "나연-이" or "나연-아" yup just plus '이' or '아' or '아' or '야' or you can just call their name.these all to prevent awkwardness. and you can use informal sentences too. and don't use like '-ㅂ니다' thing. that's it, I hope it's right or hope any advance people will answer too hahaha