"And I saw heaven opened, and behold a white horse; and he that sat upon him was called Faithful and True, and in righteousness he doth judge and make war. His eyes were as a flame of fire, and on his head were many crowns; and he had a name written, that no man knew, but he himself. And he was clothed with a vesture dipped in blood: and his name is called The Word of God. And the armies which were in heaven followed him upon white horses, clothed in fine linen, white and clean. And out of his mouth goeth a sharp sword, that with it he should smite the nations: and he shall rule them with a rod of iron: and he treadeth the winepress of the fierceness and wrath of Almighty God. And he hath on his vesture and on his thigh a name written, KING OF KINGS, AND LORD OF LORDS" (Rev. 19:11-16).
The only thing the two individuals have in common is that they ride white horses (the Greek λευκός (leukos), and ἵππος (hippos), meaning "white horse"). And while they both wear crowns, they are quite different. The crown given to the Antichrist is the Greek στέφανος (stephanos), meaning "a wreath of victory." His crown is made of organic material, and is therefore temporary. The crowns of Christ are the Greek διάδημα (diadēma), meaning "the symbol of a king's authority." These crowns are made of inorganic material, and are described as eternal (1 Pet. 5:4). Praise God, they have replaced the crown of thorns He wore during His crucifixion!
Some believe the Antichrist carries a bow because he is going forth to conquer. However, the Old Testament uses the same word for a weapon, and for a sign of peace. A bow is a weapon (Gen. 27:3), and it is a sign of peace (Gen. 9:13). Daniel describes his approach as being that of a person offering peace (Dan. 8:25; 11:21-24). Notice that Christ is described as Faithful and True, and He comes to make war. The Antichrist is a liar, and he will deceive many (Mt. 24:4-5, 11, 24; 2 Jn. 1:7; Rev. 13:14; 19:20)!
You can tell them apart by when they come. The Antichrist comes "in peace" at the beginning of the Tribulation, and the Christ comes wielding a sword at the end of the Tribulation!