I have never really understood how the lo hand works. I understand that you have to have a qualifying lo hand but what does it take to qualify? Is it the best low hand or the worst?
Omaha Hi-Lo is also referred to as Omaha Eight-or-better. The 8 is the important bit - it means that only hands where all five cards are <= 8 can play as the low.
The nut (best) low hand is The Wheel. This is
A2345. Suits don't matter - a flushing hand is the same as a rainbow. The worst qualifying low hand is
The highest card in the hand counts 'first'. By that I mean that a hand such as
A2348 is worse than e.g.
34567 - the former is an 8-high hand and the latter is a 7-high, so the latter wins. If the highest card is the same, we want the second highest to be lower, and so forth, e.g.
A2367 will win over
Edit: I forgot to mention; a low hand can only have one card of each rank. A hand such as
AA234 cannot play - only hands with 5 distinct ranks up to 8.
In high/low variants, the pot is split between the highest and lowest ranked hands. If there is a tie for one or the other, those tying hands must split that half of the pot - e.g. with one winning high hand and two winning lows, the lows each get 25% of the pot, and the high gets 50%.
In split pot games, the low hand generally has a qualifier (8 or better). This means that the low hand has to be at least as low as the qualifier. For 8 or better, the hand must be 5 different ranked cards less than or equal to 8. In Omaha, the 5 cards can comprise a straight or flush and still count as a low - this is in contrast to games such as 2-7 (deuce to seven).
As with the high hand in Omaha, the low hand must include 2 cards from the player's hand and 3 from the board.
When there are more than 3 low cards on the board, "live" cards are often read out to clarify the winner. For example, if one player has A2JQ in their hand, and another has A3TK, and the board is 25679, the player with A3TK has a "live 3", and wins the hand (6532A, vs. the other player's 7652A)
In Omaha Hi-Lo, the best hand (the Hi) takes half the pot, and the worst hand (the Lo) takes half the pot (assuming that there is a qualifying lo).
A qualifying hand is one that is 8-high or worse (if you cannot make a 5-card hand that is no better than 8 high, you cannot win the lo; in case of no qualifying lo, the high wins the entire pot).
A split game is a game in which the pot is split between the best High hand and the BEST low hand. High hand is as we all know (according to the regular hand ranking).
Low hand is considered 5 cards 8 or lower (including the Ace) with no pairs. Flushes and straights are not counted. The best low hand is A,2,3,4,5 and the worse low hand is 4,5,6,7,8.
I find a very nice explanation about it. you can find it here
The best low is the one with the five lowest UNPAIRED cards. That is A, 2, 2, 3, 4 would not qualify because the twos are paired. But A, 2,3,4,5 would qualify, because they are five different low cards. The fact that they make a straight doesn't count against it (and the straight could win high). The best low hands are the ones like these that can also win high, because the best high hand and the best low hand split the pot (unless the same hand wins both high and low, and takes the whole pot).
Low hands are defined by the highest card, which must not be higher than an 8 (to qualify). The "8" hands are the worst low hands, and A2348 is worse than 34567. Likewise, all 7 hands are worse than all 6 hands. If there is a "tie" between two players for the top card, then compare the second card in each hand, then the third card, etc. The first player with a lower card at any level wins. Only if the five cards are all equal do they tie.
Paradoxically, it's better to go for low than high, because it's quite possible to have to equal high hands that "quarter" (divide twice) the high end of the pot, but it's rare that there will be two exact lows. Plus the fact that low straights sometimes win high but high hands almost never win low.