Start sitting on a jug rail. do a few moves to find yourself within striking distance of the slopey lip. Once matched at the lip , figure out how to get yourself over it to gain a solid crimp halfway up the face. From here, stand up and find your way to the top.
Most easily access by approaching from Devil's Bay. Head North through the baths. Get your feet wet, go through one tunnel, and then one more. Once you see a directions sign, turn around (look south) and you should see the cave that Jungle Gym is in. From here, you can crawl up a hole to get on top of the boulder that makes the wall behind Jungle Gym (South of it). Jungle Jim is on an elongated boulder sitting on top of this GIGANTIC rock. This problem follows the rail coming out of the North East side of the boulder and climbs directly up and out of the cave.