Note that you need to obtain a 
Goron Tunic from Goron City in order to survive the heat in the Death Mountain Crater. Check out the previous page (Traveling to Death Mountain) for more information on how to obtain one.
Approach the broken bridge just up ahead and use the 
Hookshot to reach the wooden post sticking out from the stone wall just above the other side of the bridge (shown in the screenshot above).
Continue down the bridge and you will run into Sheikh again. Sheik will teach you the Bolero of Fire which will allow Link to transport back to the Death Mountain Crater at any time.
Warp back to the Temple of Time using the Prelude of Light and transform back into young Link. Make sure that you have some Bugs in one of your Bottles. If you don’t have any currently you can head back to Hyrule Castle and grab some from under the rocks near the pine tree at the front gates.
Warp back to the Death Mountain Crater using the Bolero of Fire. Note that you can only stay in the crater for a limited amount of time as young Link cannot wear the customized Tunics. There is a mount of soft soil right near the warp point (that was not there when you were an adult).
Place some Bugs in the mount to reveal a hidden 
Gold Skulltula (number 65 of 100). Plant some of your Magic Beans before you leave and then warp back to the Temple of Time.
You can also pick up another Heart Piece using the Magic Bean Plant:
Now it is time to move on to the Fire Temple.
