LMG- Hammer the skulk as it ocmes, then hop to one side and continue.
Pistol- AIM! small clip means that you must! (only four or five to kill a skulk....means anywhere between two and three if you hit with most of them. Three is rare, requires lmg hax....)
Knife- Don't really have a strategy, I just try and wait for good hits......occasionally i go all berserker style and hold down the button....but that almost never works.
HMG- see lmg
GL- ACtually, I think ff is an abuse for this gun. with it, you can stand behind a group of heavies shooting a fade or an onos, and then put ONE grenade into them and voila! the skulks climbing all over their faceplates are now goo! [size=8](use with caution- may result in unforeseen casualties when applied by nubs)[/size]