Walk across the street of any busy city and you can see all kinds of signals everywhere you look. Most of them are created to get your attention. Some keep you safe, some feed you information. Not much effort is needed to notice them.
Walk across a trek in the jungle and you can sense different kind of signals. They are also created to get your attention. Some keep you safe, but some are probably there to keep you away. Only those with trained and elevated senses can notice them.
Now imagine you are travelling across the universe, are there any signals out there in space to look for? I would say more than anywhere you can find on earth. It's just that we as human being has not learned or evolved enough yet to sense those signals out there.
Ever since cameras are invented, they have been a great tool to capture signals originated from the source of light. A signal can be captured on a photo which can be studied in depth, even long after the signal has gone.
So if you are still looking for a signal, why not start snapping some photos? Who knows, you might capture the signal that was meant for you.