Choose the right cut (tender cuts: tenderloin, strip, ribeye)
Pound with a meat mallet to even thickness
Use a meat tenderizer tool (spikes) for thin cuts
Marinate in an acidic or enzymatic marinade (lime/lemon/vinegar or pineapple/papaya) for 30 minutes to 4 hours
Avoid over-marinating acidic marinades (can make the meat mushy)
Use a dairy-based marinade (yogurt or buttermilk) for 4 to 12 hours
Salt the steak (dry brine) 40 minutes to 24 hours before cooking
Pat dry after salting/drying brine to improve browning
Cook to the correct doneness (use a thermometer)
Slice against the grain after cooking
Let the steak rest 5 to 10 minutes before slicing
For tough cuts, braise or slow-cook instead of grilling or pan-searing