Here's a video tutorial which also shows this process: 
http://www.youtube.com/watch?v=WiJiDPUpr98


1. Download SAAT (San Andreas Audio Toolkit). It is available to download here:
http://www.gtagarage.com/mods/show.php?id=1186

2. Copy the contents of the downloaded SAAT into your main GTA San Andreas folder (the files included in the downloaded that you need are metadata-full.ini, metadata-genetic.ini, saat_sfx.exe, and saat_stream.exe).

3. Create a folder in Local Disk (C:) and name it "temp" if there is not already one.

4. Open command prompt (go to start -> run and type "cmd" without quotation marks).

Within command prompt, use the following commands:
	


First command:
cd C:\Program Files (x86)\Rockstar Games\GTA San Andreas

This will always be the first command you enter when starting up CMD, as it allows command prompt to work within the GTA SA directory.



Second command*:
*NOTE:  You only need to use these commands once for the first time you use SAAT and for each sound archive you wish to modify. These commands just export the sounds from one of the SFX sound archives (for example: GENRL, FEET, PAIN_A) into your temp folder. You can use this for all of the sound files in audio/SFX, but GENRL, FEET, and PAIN_A contain the majority of common game sounds outside missions. If you use these commands a second time, any sounds you have changed in your temp folder will be OVERWRITTEN.

Exporting from audio/SFX/GENRL to temp folder:
saat_sfx -e audio\SFX\GENRL C:\temp\saat audio\CONFIG\BankLkup.dat

Exporting from audio/SFX/FEET to temp folder:
saat_sfx -e audio\SFX\FEET C:\temp\saat audio\CONFIG\BankLkup.dat

Exporting from audio/SFX/PAIN_A to temp folder:
saat_sfx -e audio\SFX\PAIN_A C:\temp\saat audio\CONFIG\BankLkup.dat



Third command**:
**After you have performed each of the second commands just once, all of the individual .wav files contained in each sound archive will be available in the temp/saat folder. Once you replace these files with something else (such as this mod), you will use this command to import the sounds in the temp/saat folder to the sound archives located in the GTA SA audio folder.

Importing from temp folder to audio/SFX/GENRL:
saat_sfx -i audio\SFX\GENRL C:\temp\saat\GENRL\sfx_import.ini audio\CONFIG\BanKLKup.dat

Importing from temp folder to audio/SFX/FEET:
saat_sfx -i audio\SFX\FEET C:\temp\saat\FEET\sfx_import.ini audio\CONFIG\BanKLKup.dat

Importing from temp folder to audio/SFX/PAIN_A:
saat_sfx -i audio\SFX\PAIN_A C:\temp\saat\PAIN_A\sfx_import.ini audio\CONFIG\BanKLKup.dat