Determining low in omaha

How do you tell low? Do you count from low to high or high to low ie
Which hand wins low 87621 or 87532? do you start at the eight or the ace? Also if you have ace duece in your and low is on the board is it a guarentee you have low? thanks from a rookie.

You look at the highest card of the 5 first. If those are the same you go to the 2nd highest. And so on down to the lowest.

So in your example, 87532 wins because the 8 and 7 cancel out. Then the 6 plays and it's higher than the 5 in 87532.