Prophet Muhammad used to recite out loud in Fajr prayer, the first two Rak`ahs of Maghrib and `Isha’, and Jumu`ah prayer. He would recite quietly in Dhurh and `Asr prayers, the third Rak`ah of Maghrib prayer, the third and fourth Rak`ahs of `Isha’ prayer.

It is not permissible for you to pray sitting down in obligatory prayers unless you are unable to stand, or standing is very difficult for you, or you are sick and there is the fear that your sickness may become worse if you pray standing up. It is permissible to pray sitting down in optional prayers, even without an excuse, but the reward of the one who sits in that case is half the reward of one who stands

There is no doubt that shoes are big and three dimensional, but they should not be used as a Sutrah, because shoes are customarily regarded as dirty, and you should not have them in front of you, when you are standing before Allah.

Subhana Rabbiyal Azim means glorifying the One Who possesses ultimate greatness. Subhana Rabbiyal A’la means glorifying the One Who is exalted in His Essence.