All the rules and game play is exactly the same as in the standard 7 Card Stud Poker. There is also the Buy-In, you also receive two cards face down and one face up in the first round. The same rules (Bring-In etc.) for betting and who acts first apply. There is also a fourth, fifth, sixth and seventh Street round with each round's betting determined as in the normal 7 Card Stud Poker.
The only difference is that in the Hi-Lo version of the game, at the Showdown, the player with the highest (Hi) poker hand wins halve the pot and the player with the lowest (Lo) poker hand wins the other halve of the pot.
BUT, to qualify for the Lo, the player has to have no card higher than 8 or else he cannot win the Lo pot.
What makes this style interesting, is that even if you are dealt cards that you can really not win the Hi with, you still stand a chance to win the Lo. You also do not have to specify if you are playing for the Hi or the Lo.
So you can either be the biggest winner, or the biggest loser and still win something!