Translated from Chinglish. If you can do it then you should go up and do it. It's used against people who criticize others' work, especially when the criticizer is not that much better. Often followed by "no can no BB", which means "if you can't do it then don't even criticize it".
中式英语翻译而来。如果你行，你就应该去做这件事。这句话用来讽刺那些挑剔别人工作的人，尤其是那些自己本身也做不好的人。通常这句话后会跟着“不行别逼逼”，意思是“如果你做不了，就不要挑别人的刺”。
【例句】
"That person does not deserve the award."
“那个人不应该得奖的。”
"You can you up."
“你行你上啊！”