I'm a n00b in textures, and how do I get realy nice textures?

Do I replace the textures that already exists. (qw/textures?) Or should I put them in a map and start quake with (ex. -game textures?)

if you download a map specific texture pack, you put it in qw/textures/<mapname>

if you download a large texture pack, put it in qw/textures and replace any textures currently there

here are the different folders where the different textures go

qw/textures/ — Map textures
qw/textures/exmy/ — Map textures for the original single-player maps
qw/textures/<mapname>/ — Map textures for <mapname> (e.g. aerowalk)
qw/textures/bmodels/ — Health/ammo box textures
qw/textures/models/ — Model textures
qw/textures/charsets/ — Console characters
qw/textures/particles/ — Particle textures
qw/textures/wad/ — HUD items
qw/crosshairs/ — Crosshairs
qw/env/ — Skyboxes

Thanx man!