What do I do as a "non carry-able support" if no one on my team is doing well?

e.g. Soraka or Janna? Like yes, Lux, Brand, Vel'Koz, Zyra and Xerath supports have a pretty great chance of "carrying" if played well, but what about more traditional supports? What am I supposed to do? And please don't say "just play supports that can carry", I already really like Lux and play her relatively often, this question is specifically for cases in which I am not playing a 'carry support'.
Report as:
Offensive Spam Harassment Incorrect Board