I drink tea with lemon and ginger (fresh or crystalised ginger works, but not dried). You get some antioxidents and some antibacterial stuff (colds aren't caused by bacteria but secondary infections can be), and it makes you feel good. You can put your echinacia tincture in there if you like.
I also go for the symptomatic treatments. Painkillers and decongestants, yay! I used to be one of those people who struggled through unless my head was falling off, but now my theory is that feeling good allows my body to work more efficiently. It might not work like that at all, but not feeling miserable is always a good thing.
Unless I'm too weak to leave the house, mild exercise like walking to the shops seems to help. Make sure you're wrapped up well enough to keep your nose warm, though.
Zinc is supposed to help, along with vitamin C obviously.
If your throat is irritated, any warm liquid or stuff that makes you produce saliva helps. I like chewing gum for the latter, especially if I'm out and about.