You don't.
The good part is that if they do simply wet it, wait a couple minutes and wipe it off easily.
Reference:
Cleaning bird poop off my floor every day from my pet birds.
One way to have birds to stop pooping there is to make sure to remove all bird feeders in your area. You also don't want to put a lot of trees in the area of your verandah.
by pooping
This fear is called Ornithophobia. the fear of birds.
You can create a cozy outdoor seating area with chairs and a table, tend to a small garden with potted plants, enjoy a cup of coffee or tea, read a book, or simply soak up some fresh air and sunshine.
kill them
There is a product out there called Bird-Deter that is specifically designed for use on a mailbox. It is a very simple design but it keeps birds off of a mailbox with harming them in any way.
To deter birds from pooping in a decorative fountain, consider using physical barriers such as netting or spikes to make the area less accessible. You can also try adding reflective surfaces, like aluminum foil or shiny objects, which can scare birds away. Additionally, placing decoys of predators nearby or using bird repellent sprays can help keep them at bay. Regular cleaning of the fountain will also discourage birds from returning.
yeah kill it
Because u have to get it out of your system
Unless the birds are causing harm to the balcony let them nest there. If their staying there is undesired wait until babies are hatched and gone then remove the nest and block where they are nesting.
Drop it off a balcony
tell your poo to toughen up?