If you are wishing someone general good fortune, you can say: Best of luck Best wishes I wish you all the best May the force be with you (you would say this in a jovial situation. This phrase references Star Wars, a popular American movie, and most Americans would understand it) If you hope someone does well in a performance or a competition, you can tell them: break a leg knock them dead fingers crossed Godspeed Go and get 'em (them)

Well, we know that by saying good luck, we mean to be successful...! So, there's another idiom for good luck, which is "MAKE GOOD". It's meaning is same as that of good luck. e.g., "I wish you MAKE GOOD." Which means I wish you to be successful or, you may say this "good luck"...!