I don't mean to sound too dismissive but a lot of the above advice won't have much, if any, effect. The steaming is good, not because of pores opening but simply that viruses aren't good at higher temperatures - part of the reason we associate colds with cold wet weather is that cold viruses like those conditions. That's why the steaming, and hot drinks (yes, in this weather!) are good.
Zinc that you can actually get into your throat, either by a drink, powdered form or a suckable/chewable tablet, is very good - it's one of the few things that's been shown to have an actual biochemical mechanism for de-activating cold viruses.
Someone said about GPs recommending echinachea? That conflicts with research findngs I read about 2 years ago saying that no evidence had yet been found for any positive effect of echinachea. But make your own mind up. It's never seemed to do anything for me. I've done quite a bit of research on the common cold (I've been writing a book about it), and here's something I bet no-one here will believe - there has NEVER been any evidence to support the idea that vitamin C does anything to keep colds at bay or lessen the symptoms. Citrus fruit and other vitmain C rich foods are good as it is an important vitamin for lots of other things but nothing's ever been found to support the notion that it helps to battle colds.
Unfortunately, given that you're busy for a few days, the other helpful thing to do is rest and take it easy - but it sounds like that's not going to be possible for you. And, ultimately - as has been said - once you have the cold, all you can do via the above suggestions is make yourself as comfortable as possible and keep the symptoms under some control but you can't escape it.