Birds poop. and your GCC has pretty tiny poop.. can't imagine your mom living with a too..
It is possible to train birds to poo in certain areas or on command, but it can be very detrimental to the bird and their health.
Easiest thing? just rip off bits of Kleenex and clean up the poo.. or wear a "poo shirt"
Birds tend to poo right before take off, but also for small birds, they can go every 5-15 minutes if I remember correctly.
I always just keep Kleenex around or a shirt or rag I don't mind and clean it up.. I can always wash stuff. If your bird has certain spots it likes then lay newspaper down.. or if it's the back of the couch put a towel up.. or fold/cut a shower curtain to fit it better..
But the best answer is "No. you can not stop a bird from pooping. doing so will cause them to have issues."