depends on the reason why your sound doesn't turn on, and what aspect.
If it's a KDE thing, run kmix, configure the volumes, and don't quit. Killing arts will also do some good (in the kde configuration)
If you're not using KDE, try getting alsactl restore to run on startup (you'll need to configure alsamixer and run alsactl store).
If it's global investigate what module the sound runs off, and add it to /etc/modules.conf
Alternatively, compile a kernel with the sound module statically compiled in.
BUT it all depends on what your soundcard is, and what you've already tried. Any more details?