Ick! Colds/allergies/sinus infections are the total pits since I've had IIH! The extra pain and pressure of the sinus congestion on top of an already-pressurized head can feel like torture. I feel your pain! *hugs*
First of all, it was helpful to me to ask my doctor what I could take. For instance, I had always taken Allegra-D, but he suggested I switch to plain Allegra, since the decongestant in the "D" might actually cause in increase in my IIH symptoms. Secondly, it helps me to do whatever I can to relieve the congestion in my sinuses/ears ... my two favorite things to use are cold cloths over my sinuses, and a vaporizer or a vapo-rub with the eucalyptus to help clear the sinuses.
Other than that, it's just resting and waiting it out, unfortunately. At the first sign that it may be progressing to a sinus or ear infection, I always get to my GP so he can assess if antibiotics are needed. Hopefully it won't get to that point for you this time though! *hugs* Hope these suggestions help and hope you feel better really quick!