What is the best way to prepare and cook steak for fajitas?

The best way to prepare and cook steak for fajitas is to marinate the steak in a mixture of lime juice, garlic, and spices for at least 30 minutes. Then, sear the steak on a hot grill or skillet for a few minutes on each side until it reaches your desired level of doneness. Let the steak rest for a few minutes before slicing it thinly against the grain. Serve the sliced steak in fajitas with sauted peppers and onions.