What's your symptoms like?

I agree, sitting around doing nothing isn't going to help you recover. You should try to get out and at least get some sun and fresh air. The simplest thing, but you can't overlook how important that is. Honestly, from my experience it's the best thing for a concussion that lingers.

Get your diet in check, proteins, veg, no processed junk with additives.

I went off caffeine for ages after my concussion (I'm a tea drinker). Honestly felt it did nothing good for me. 'm definitely a person that doesn't like being told I can't do something, so just going back to my usual tea felt good.

I've just stayed off alcohol, but I'm not a big drinker anyway so don't really care.

Try Acetyl-L-Carnitine (500mg at Vitamin Shoppe). Plenty of studies backing this up, got the tip from guys at the gym, a few of them had used it in concussion recovery with good success. It certainly helped me, felt like my mental clarity came back a lot and my mood improved.

I was in bad shape in the summer, well on the way back now. Any other advice you need, feel free to buzz me.