From StrategyWiki, the free strategy guide and walkthrough wiki

Head north and grab theKey, then go north and kill the giant bats for anotherKey. Head north and grab the Compass. Head north and bomb the north face. Head north. Kill the boomerang bears and push the left-hand block aside to open the door. Kill the Darknuts and push the left-hand corner of the diamond aside. Go down the stairs to claim the Raft. Go back upstairs and head south twice, then east once. Kill the giant bat for some Bombs. You need at least one bomb for an upcoming area, so be sure to save one. Head north and kill the Darknuts for aKey. Head back south and unlock the door. Head through it and bomb the east face. Head north to fight the boss, Manhandla.

The strategy is simple: using your bow, shoot at each of the heads to destroy it, then move onto another. It takes about two shots to kill a head. After each head is destroyed Manhandla moves a little faster, and is very fast near the end. Bombs may work well at this point. When you've killed it grab the Heart Container and head north for the Triforce piece.