Teleport to the 'jungle campsite', go to the right and up the vines. You want to keep going upwards and to the right as much as you can, cross stepping stones and up more vines.
Once you reach the top of the waterfall, head left and keep jumping... you should be able to figure out the path from there!
You need to synthesize the materials for it from the Wizard at the inn. To synthesize, you need the cauldron. Hopefully you picked this up... if not, it can be found from a merchant on the other side of the slug den. Make your way back down there, and follow the path through to the other side (DON'T go back down to the core).
Synthesize the 'straps' using materials you can gather from slugs, and shambling mirages (desert valley). Take the item to the blacksmith at the camp... and he should whip something up for you right quick!
