Watch the sponsored videos!
At the highest, the videos give you 5 GCash, you usually get it in about, 20-25 second, unless the vid itself is 30 seconds. You don't even have to watch it. The most from that is 30-40 GCash. They stop giving you the 5 after a while.
Then after a long time stocking from videos, they tend to have you open some web stories. You don't even have to explore those, just click one and go back to the Gaia tab.
Or if you have a facebook, there should be some games you can play, (they have something for you to reach until you get GCash) and that shouldn't be too much of a hassle.
I'm gonna be honest, I spend about 30 mins just stocking up. c: