Hello! Today I will be showing you the most efficient way to create your very own Minecraft Soundpack. I am aware that there are other tutorials about this out there, but some are outdated and some are completely inefficient and time-consuming. So, here we go!    (Just so you know, I will only be outlining how to change and edit the sound files. You can find how to mess with the textures, pack.png, and pack.mcmeta elsewhere.)

Resources needed:
-7zip or Winrar
-Minecraft
-Sound files for your pack
-Audacity program (optional)

STEP 1:
The very first thing you must do is get a default resource pack. You can do this by extracting some things from your .jar file, but just to make it easier and not overwhelm you at the start you can download the default pack here: http://www.mediafire.com/download/ctcupdvntf68uv0/1.8+Default+Resource+Pack.zip

STEP 2:
Next, you must extract that resource pack (using 7zip or Winrar) so you may edit the files. After that go into your assets folder and create a new folder called "sounds". It must be named that exactly or else your sounds will not work. 

STEP 3 (THE BIG ONE):
Create all the folders necessary for your sound pack. You will find this link CRUCIAL to your creation of the sound pack: http://minecraft.gamepedia.com/Sounds.json

The chart there outlines EVERY sound file in the game, since they are not, by default, in any texture pack. 
So, let me show you how this will work:



Let's look at this section of the chart. The two columns you will need the most are the "Sounds Used" and "In-game Events", the ones I have squared out here.
The first red-outlined column tells you where your file will be. So, it will be in a NEW folder in the sounds folder. That folder must be named "damage". After you have created this folder, go into it and put the sound files you want for "A player taking damage". The sound file you place into the folder must be a .ogg file; you can find mp3 to ogg converters online or you can use Audacity to convert them.
After you have placed the .ogg files into your folder you must rename them hit1, hit2, and hit3.

You must go through this process for every possible sound in the game (over 500) if you want to make a complete sound pack.

TIP: If you only have one sound file that you want to use for the player taking damage, then simply use three copies of that file and rename them hit1, hit2, hit 3.

STEP 4: 
From there you must create every folder that the website lists, if you wish to change every sound file.
If you don't want to change the sound a cow makes, then you don't have to make a cow folder in the mob folder.
There are A LOT of sound files available to edit. So, don't think that making a sound pack is easy; it takes just as much time as making a texture pack.

STEP 5:
Optimize your sound files! You may put your custom sound file in for a wolf, but when you go meet a wolf in-game you might find that you can barely hear it. This is where you use Audacity (or any other sound editing program) to make it louder, or add effects to it. This part is key, although a lot of people may skip over it. You will definitely find that some of your files are way too loud, too high pitched, or simply just not suited to your pack.
You can find Audacity tutorials here: http://wiki.audacityteam.org/wiki/Category:Tutorial

STEP 6:
Get valuable feedback! Post your pack to PMC or some other Minecraft site and ask for criticism. One of the best ways to improve is to hear what other people think about your creation.


Confused? Didn't understand something? Think I missed a key point? Want me to give another example? Tell me! I will do my best to help you!

Thanks for reading!