If it's spring or not to hot you can stick em in a dome outside in the shade, but outside of that you really need a second box or at least, a CFL. You don't have to setup an elaborate grow cab or anything for the cuttings, but they need mild light, moisture and air circulation like any other plant.
I'm no fan of domes personally, even though the leaves don't do a heap of growing while the plant is rooting, a light breeze at least is essential to prevent mould and clear the leave-surface allowing it to breathe. Humidity domes stop this happening, and are generallly more of a pain in the arse than they're of benefit.
Edit: How dry your air is will determine whether a dome will be bad or good for your cuttings, if you're in some super-low humidity summer heat, a dome of some kind will be of benefit, but, if the air isn't too dry, then they'll be the death of the cuttings.