Well i always have run mode on and i have precise aim. It took a little to get used to but its worth it.
I have a couple of tips of my own that should help out some people:
1. Try and corner someone with a shotgun. While running towards them shoot and kick at the same time. Instant kill.
2. In an 8 player deathmatch and there is a massive battle in the middle of a level, grab a decent weapon (devestator, Shotgun, RPG etc) and wait for people to be at their weakest and bunched together. A couple of well placed shots can give you a massive amount of kills.
3. Always carry around a medical kit with you. Especially during one on ones. Having that extra health at times is critical to grab that kill.
4. Once you start firing at one person, stick to trying to kill them. If someone else comes along and you decide to shoot them instead it puts you in a difficult position. The other person is in a critical state and they might end up killing you instead.
5.Use Holoduke! Even if it fools your opponent for 5 seconds thats all you need to blast a few easy rounds into them.
I know they arent exactly great tips but thats what i use when i play online and i have been successful while using them.
EDIT: I am playing online now. I hope to run into some of you soon
