［miàn tiáo］is correct. when you use pinyin，you need to follow several rules. And you can remember this pattern when you don't know where tone markers should go. 1.When there letter "a",put tone marker on "a". 2.If there isn't "a",then you should put tone marker on "e"or "o". (That's why we write 泪 [ lèi］but not leì.) 3.When there are both "i"and "u",put the tone marker on the letter at the last. (Such as 推[ tuī］and 留[ liú］.） 4.when there are letter "j" "q" "x" "y" ,you need to write letter "u" instead of letter "ü" after them. I hope this can help you ; )

it is matter for you when you have started to learn Pinyin. 面条（miàn tiáo) is correct. when the character three phonetic letters we put the tone at the fist letters of the third phonetic. As miàn(m+i+an)