EmergenC - that stuff is amazing. Lots of tea (with honey if your throat hurts), chug water, extra sleep if you can. I was also all about the green smoothie when every one around me was getting sick - as much spinach as I could shove in there.
I had a nasty cold come on in May (and mine always seem to turn into sinus infections), but it was gone in 2 days! I drank a ton of water, took DayQuil to lessen/get rid of my symptoms during the day (horrible sinus pressure, etc)., sucked on throat lozenges for my slightly sore throat, and rested and rested and rested. I was working, but would come straight home and lay on the couch all night...while drinking water and sucking on lozenges and taking DayQuil. I also blew my nose a lot to get the crap out.
Don't know if it was coincidence or all this really helped, but after 2 days of feeling like crap, it was just.....gone.
Hot and steamy showers. They donto keep the cold at bay, but keep the mucous loose and it's easier to cough/blow out, thus leading to less of a head cold.
I start taking Sudafed right away so I can avoid the sinus infection that will inevitably arrive if I don't beat it early. And vitamin C/zinc supplements.
I also call in sick the first day, I have tons of sick days and spending one day in bed right off the bat really helps get rid of it faster.
I buy the chewable vitamin C in the vitamin section. I can't remember the brand but its the one in the brown bottle with the yellow label. Then I eat a ton of it while drinking a ton of water.