If he has a runny nose you can put saline drops up his nose to help clear it. Also put the yellow pages or something under the legs at the head of the cot to prop it up a bit.
Whenever DS has a snuffly nose we use a vaporiser. When it's been really bad though we've taken him into the bathroom while the shower is running hot.
Other than that there really isn't a heck of a lot you can do for bubs that age