One should be aware of the fact that G-d always stands near him and observes his doings, for G-d fills the whole earth with His glory. Therefore, one should be cautious at all times to keep his behavior, affairs, and speech at their very best, since he is in the presence of the Great King, the Almighty.
Upon awakening, one should consider the mercy of G-d, who graciously restores man's invigorated soul to him each morning.
To express this gratitude one should say the following prayer called Modeh-Ani:
מודה אני לפניך מלך חי וקים שהחזרת בי נשמתי בחמלה, רבה אמונתך
"I thank Thee, O living and eternal King, because Thou hast graciously restored my soul to me; great is Thy faithfulness."
Yehudah, the son of Tema, said: "Be strong as a leopard, light as an eagle, swift as a deer, and mighty as a lion to do the will of thy father who is in heaven."
"Strong as a leopard" means that no man should be ashamed if people should mock him for serving G-d.
"Light as an eagle" refers to the vision of the eye. Be swift to shut your eyes from looking at evil things, for this may lead to sin.
"Swift as a deer" refers to the legs. Your feet should run swiftly to do good.
"Mighty as a lion" refers to the heart. A man should strengthen his heart, by conquering his evil inclinations, and engage only in the service of G-d.
As soon as one awakens, he should be ready to serve his Creator.