1.Stay near your teammates,if you get seperated even a small mob of common infected can forget your stuff up.
2.SHOOT loving SMOKERS AS FAST AS YOU CAN,THESE mondayS WILL KILL YOU.
3.Do not. EVER. Melee kill a spitter.
4.When you see a charger,move away from any drop instant kill spots,such as windows in the hotel.
5.Try not to get hit by the charger also,it can seperate you,and #1 can happen.
6.Don't be a hero. Being a hero can literally forget your stuff up. RUN FROM TANKS,DON'T GO BATstuff WITH A MACHETE,THAT'S BEING A HERO.
7.Adrenaline is indeed better if you have low health,as it gives a health boost (although temporary and lower than the pill's) and gives a temporary speed boost,as speed is deprived from you when you're low on health.
8.Listen for sounds. These telltale sounds can help you keep your ass on until you get to the saferoom.