Dodongo Cavern: King Dodongo --- This boss is easy. Just Z-target him and get a bomb ready. When he opens his mouth to blow fire at you, throw the bomb in is mouth. He will start to wine and fall down. Then you can hit him. He will get up and try to roll you over. Z-target him and hold the R button. It will look cool when your shield blocks the rolling dino. Repeat until dead.
Jaba-Jabu Belly: Berinade --- This boss hits you a lot. So go in with a full supply of healers. Fairies and milk? Z- target him and keep throwing you boomerang. Move around him constantly to avoid being zapped. Try aiming for the tentacles first. This may not sound too assuring, but it worked for me.
Forest Temple: Phantom Gannon --- This guy has two phases. First he will go into the pictures. Get an arrow ready and keep scrolling from picture to picture. One of the gannons is fake though. Look for the one that rides slightly to the right on the path. When he starts to come out, (a lot of purple light) hit him with an arrow. You know that you succeed if he doesn't hurt you. After you hit him 3 times, he will come out and fly around throwing bolts at you. Use your sword and reflect them back. If you rally it more than 10 times, give up and side-step your way out of it.
Fire Temple: Valvagia --- This dragon has 3 attacks. If he comes out and tries to swipe you, smack him with your hammer and watch him cry. Then give him another hit with your hammer, sword, or a bomb. If he comes out and flies around trying to hit you, just Z-target him and raise your shield. If he comes out and goes out of view to throw rocks on you, just stay put and stay away from the hole he goes back into.
Water Temple: Morpha --- This boss is kind of easy to compensate for the hellish water temple. Just run away if he tries to grab you. (he will turn into a tentacle) When you are far enough away, try to hookshot the red thing he turns into. If you fish him out, start whacking him with you sword. If you're lucky, you will trap him in the corner and you will win by just hitting him because he won't be able to get out.
Shadow Temple: Bongo Bongo --- I think this boss was the hardest. Just Z-target the hand and shoot arrows at them. By the way, you will need A LOT of arrows. When you wound them both, put up your lens of truth so you can see the eye. The eye will move toward you so prepare a good orange spin slash. When he is near, (this will require timing) let the spin go and you might score. Then just hit him like there is no tommorrow.
Spirit Temple: Twinrova --- These two witches look hard and fast, but they aren't. Get on one of the side platforms and wait for one of them to shoot. Just use your mirrow shield to reflect the shot of ice or fire. Then aim the reflected stuff toward the other sister. When they want to get serious, they will combine. Then you will have to absorb 3 of the SAME kind of shot to reflect it. If you absorb 2 fires and try to reflect a blast of ice, yo will suffer major damage.
Final Boss: Gannondorf --- Just put on your hover boots and move to a corner. When he shoots at you deflect it with you sword. Just like the phantom gannon. This time it will be more like a tennis match though. If it goes back and forth more than 15 times, get away. You are risking too much of your life. If you ace him, he will hang there like a balloon. Then aim and shoot him with a light arrow. Try not to miss. If you hit him, his balloon form will bust an he will kneel on the ground. Move onto his platform and beat him. When he gets up again, quickly move to your corner. After a while, he will charge up and throw six of the fireballs at you. When you see him charge up, start a spin slash. Use the spin slash to deflect all 6 balls. Finish it off like you did the rest.
Final, FINAL Boss: Gannon --- This guy is the 2nd hardest boss. Z-target his head and shoot a ligh arrow. He will be stunned. Then hit his tail. He will get faster every time you hit him. You will probably have to refill life and magic a lot of times. Good luck.