During the drafting process, so many writers start with their character's morning routine that it has become a cliché. And while you may have begun in medias res—in the middle of things—in the sense that you've put the reader in the middle of the action with that blaring alarm and desperate fumbling to turn it off, you probably haven't begun close to the heart of the story's conflict. And that's firmly where you want to situate your reader to truly begin in medias res.
That morning routine is a tempting place to start. It's the beginning of a day, after all, and a character's choices in these activities can certainly be revealing. Someone who leaps up and dashes out the door in the clothing he slept in without brushing his teeth is much different than one who prepares and eats a three-course gourmet breakfast, then bathes and dresses meticulously just to go to the grocery store. But characterization shouldn't happen in isolation and you can accomplish that equally as well—if not more effectively—by showing that character in action closer to the conflict.
Jhumpa Lahiri's short story “A Temporary Matter" starts like this:
The notice informed them that it was a temporary matter: for five days their electricity would be cut off for one hour, beginning at eight P.M.The lights go out, forcing the young couple—Shoba and Shukumar—to eat together after many evenings spent avoiding one another. This is the very occurrence that sets the action of the story into motion.
William Carlos Williams' short story “The Use of Force" opens like this:
They were new patients to me, all I had was the name, Olson. Please come down as soon as you can, my daughter is very sick. When I arrived I was met by the mother, a big startled looking woman, very clean and apologetic who merely said, Is this the doctor? and let me in.
The story unfolds to show what happens on this house call, a struggle of power between doctor and patient.
Bharati Mukherjee's short story “The Management of Grief" begins:
A woman I don't know is boiling tea the Indian way in my kitchen. There are a lot of women I don't know in my kitchen, whispering and moving tactfully. They open doors, rummage through the pantry, and try not to ask me where things are kept. They remind me of when my sons were small, on Mother's Day or when Vikram and I were tired, and they would make big, sloppy omelets. I would lie in bed pretending I didn't hear them.
This opening offers intrigue. Who are these women? Why are there in the narrator's house going through her things when she doesn't know them? We learn soon enough that the narrator's has lost her husband and sons when the plane they were traveling in “broke in two" and these people in her kitchen are friends of friends and well wishers trying to help in her time of need.
In an early draft, you may find that morning routine is a useful place to start in order to get into the story. Unless it's vital to the conflict, it shouldn't stay. Revise that opening once you've gotten through the first draft and have a better idea of your intentions for the story.