Hi, Caponi. There are many websites that will illustrate and explain exactly what you need to do. Better to go to one of these sites where the explanations are prepared and included with photos and diagrams. Here is just one:
http://www.icepoint.com/guitar/Setting%20up%20your%20electric%20guitar/

However, the Quick & Dirty for a Les Paul set up is

Set relief to .005 - .012" (.012 is factory, .005 is leaner & meaner if your style and instrument are capable. Most experts will aim you as flat as you can get it.)

Set action as 2/64" on the treble E, up to 4/64" on the bass E. (I forget what factory setting is offhand). This is a starting point. From there lower your action (if you want it lower) as far as you can or raise it to eliminate buzz. With TOM bridges this is pretty easy.

I recommend slackening your strings before making any truss rod or bridge adjustments.