Go to an place where there are white elephants. Bring with you a

muffin (with raisins). Climb a tree. When the white elephant is close,

drop the muffin (with raisins) in front of it. The white elephant will

be happy, and eat the muffin (with raisins). White elephants like

muffins (with raisins). Repeat this procedure for five days in a row.

After the fifth day, the white elephant will be used to its daily muffin

(with raisins). The sixth day you climb the tree, bring with you a muffin

without raisins. Drop the muffin as usual. When the white elephant finds

out that the muffin lacks raisins, it will darken in anger.

And then you catch it the same way as an ordinary grey elephant.