alpha is simply number 1 (literally translated from the greek alphabet), first in line of status, leader of a group, main person in a group, highest in picking order,
now how you project this status, and how status is seen, is completely relative to who is observing and what they value as a symbol of status (could be mainly one thing, could be multiple things)
think of the ideal perfect guy, there you go, that guy is probably as alpha as it gets, most commonly success in life reflects status, confidence, money, looks, power, fame, sense of humor, intelligence, security (emotional and physical)
^ and a lifestyle that reflects success to what ever niche you are trying to build status with, if you are the highest status of a group, you are the alpha of that group
status is subjective to what a person deems as successful ''winning'' qualities (as the sheen would say), also known as, what a person ''values''
if you're asking me, the perfect alpha is easy to describe, the guy would obviously live an illustrious lifestyle and have alot of life experience, he would tame tigers with a whistle and quell thunderstorms by letting a fart rip, every girl for a mile would get wet as he passed doing 3000mph in his jet-ferrari-veyron that he had specially designed for him with only 2 weeks notice, although it's no big deal for the car companies to furiously put this piece together, after all he dropped 2 trill on the thing, pocket change really, the man is so famous even natives in the rainforest with no outside contact to the western world have heard of him, and he bench presses 2 buicks with ease when he hits the gym (after all, plates are for bitches when you can use cars), and as he is lifting up the 2 tanks after the warm up, he gives advice to all the guys in the gym and they all become rich and famous as a result, after hitting up the gym this guy would return to his harem of hundreds of thousands of girls, and have them all fighting each other and worshiping him as he drops his pants to reveal his huge 20ft long dick, and it's not that it is 20ft long that is so impressive, it's the fact that it is made of the finest swiss chocolate and ejaculates money and diamonds, but meh, it's no big deal to him, having this kind of life is easy when you're an alpha male