Know what rates to use

To change or check your rates, pull down your gameconsole and type one of the following commands:

rate
cl_updaterate
cl_cmdrate

For modem user they should be:
rate: Around 3000 to 5000
cl_updaterate: Around 20-30
cl_cmdrate: Around 20 to 30 also

Broadband or Cable users should NOT use these rates, instead, they should be:
rate: Around 16000
cl_updaterate: Between 80 and 101
cl_cmdrate: Also between 80 and 101

if u ping high and u wanna make u hits reg better use something around

cmdrate: 90
updaterate: 90
rate: 20000

also nice comands to improve gameplay are

cl_particlefx "0"
and

hud_fastswitch "1"

particlefx makes the smoke from the bazooka disappear.. it may be hard to see the shot flying but makes ur gameplay after the shot is fired much easier... and fastswitch is so u can use a button to flip between ur one shoot-kill weapon and pistol to lower the loading time of the gun.