It's a bit of a scramble down from the parking lot, then you need to climb up over some boulders to reach the main pool.
The levels were a little too low to warrant a swim, but the falls still generated plenty of water for an impromptu refreshing shower. You're also able to follow the river's course downriver a little to some more pools.
A visit to Huang Num Kaew works well when combined with a visit to the big tree and 200-year-old tree as they're all within a short ride of one another. The waterfall isn't signposted for much of the way -- follow the signs for the trees instead -- and just keep going. When you reach the big white concrete rest area, you're there.