안녕하세요? 저는 치안인데 기퍼가로 불러 주세요. 저는 데일리룩에 처음이에요. 패션 마음에 들어요...만나서 반가워요! ^^
I usually use 존댓말 (in informal polite => -요) especially when I am meeting new people. The usage of formal polite (-ㅂ니다/-ㅂ니까/-십시오) are used in newspapers, books, used in tv or radio broadcasts, and if you are giving a speech. So, just use -요 ending! It also shows a more approachable way of trying to get the interest of anyone. Also you should practice consistency in your paragraphs, when you use -ㅂ니다, then all the rest should be like that too, or if it's -요, then every sentence should end like that. Then when you use 반말, then you can eliminate -요. I also have to add, it is much safer to use 저 than 나. 나 is in 반말 speech, so you only use it to someone who is of lower status than you or to your close friends or family. That's why to be safe, if you want to use -요 as an ending, then use 저(는) and not 나(는). :)