Getting A Good Sound
Getting a good sound for jazz on guitar is a combination of your equipment, settings on your electronics, and you as the player.
If you want to sound good playing jazz, you need to listen to great jazz guitar players.
Spend some time figuring out what you can do to match the sound of guitarists like Barney Kessel, Wes Montgomery, Joe Pass, and Jim Hall for starters.
Your equipment also plays a part in the sound you create with it.
Having the right strings and picks, the guitar and amplifier you use, and knowing how to adjust your tone and volume settings can all make a big difference.