Explanation of the author's statement: "...and covering his face..."

The Shaykh : He said, "It is also disliked to cover one's face". It is disliked for a person to cover his face while praying because this may lead to confusion, and because when he prostrates, he will place a barrier between himself and his prostration. Therefore, this action is disliked. However, if he needs to do so for a reason, such as sneezing, for example, if he wants to sneeze while praying and needs to place his garment over his face in this manner, then a pressing need makes the disliked act permissible. An exception to this is a woman if there are men around her who are not her mahram (relatives one may not marry); in that case, it is obligatory for her to cover her face, and it is not permissible for her to uncover it.
The author said, "and the latham over his mouth and nose". The latham over the mouth means to cover the mouth in this way, meaning to place the turban, the ghutrah, or the shemagh over the mouth, and likewise over the nose.