Have your beans and rice already made, seasoned and warm. For Mexican style rice, you can cook the rice in chicken stock and add in ¼ tsp garlic powder, ¼ tsp onion powder and a tsp of tomato paste. Optionally you can add chili powder and cumin.

Mise en place, have all your cheese, salsa, onions, cilantro, etc prepared and ready for the final wrap.

Sprinkle the steak with garlic powder, onion powder, salt and pepper. For authentic flavor, grill the steak for 3-4 minutes each side (depending on how thick it is) and let it rest for 5 minutes.

You don't want your tortilla crunchy before you roll it! If you are unable to steam your tortillas, the next best way is to warm them up slowly on a flat top, (in a pinch use your oven set at 300°F., no need to flip add cheese right away) once both sides are warm and the tortillas is much more flexible. If you're using cheese, add it now, both slices next to each other in the center so it fully or partially melts (since the heat of the rest of the ingredients will melt it the rest of the way. Remove from heat. (I have seen Mission burrito makers put the final rolled burrito on a flat top, but you better be really good burrito roller for your ingredients not to come spilling out!)

Lay out the tortilla and place beans on top of cheese covering only the bottom third of the tortilla, (drain liquid if they are whole beans). Now add the rice on top, evenly across the entire layer of beans.
Chop the steak (or chicken) into bite size pieces about ¼ inch, add to the top of the rice.
Add any extras in on top of the meat like cilantro, onions, salsa or some extra shredded cheese. You see we are sandwiching the ingredients that we don't mind hot and the last ones are chilled and on the outer edge once we wrap it. Top it off with sour cream and guacamole if you are using it.

The Roll (Here's a 23 second video on YouTube from Thrillist.)
Pull the two sides up, half folding in, while maintaining those sides with bottom three fingers, now use your thumb and fore finger on each side and grab the bottom of the tortilla, pulling it over the ingredients, while tucking in the side and finish the roll by tucking it all in evenly in one swift movement.
Place on top of some aluminum foil wrap and wrap up closing the bottom off from any drips and the top you peel away the foil to eat a few bites at a time. Always leave the foil on the lower portion to keep the structure of the burrito intact until it's time to peel away the foil and eat the next bite burrito! Enjoy!