To start with, create a skeleton which walks left from your starting location and stands on the blue button there. That should let you get past the gate above the button.
Yes, but then where do I go? I'm stuck, after that point. There seems to be nothing I can do with the skeleton, or my character, and it doesn't open up any materials for my character to collect...
After going through the blue gate and activating the checkpoint to replenish your resources, you can send a skeleton to the left to hold down the pink button in the water. Make sure the skeleton has a long enough run up so it can fall into the water.
