Помогите, пожалуйста с английским, где обязаны находиться фразы выделенные красным? Ref:...

1. To begin with, references are usually printed on the left. 
2. However, when indicating the subject of the letter, we generally use the subject line: it appears below the opening salutation. While references are used for other purposes (they consist of the initials of the person who signs the letter and those of the typist, for instance). In other words, I recommend you should stipulate the subject ("order ..." in your particular case) not in the references but in the subject line. I'd also omit "our": stick to the "telegraphic style"! :)
3. Signature is put under the complementary close on the left, but there should be a blank line between them.