Okay so! I have been in your place, accidentally spending around 500k silver without realizing and suddenly OH NO I'M BROKE.
The fastest way for you currently to earn money is to Explore. Higher level pets will get you more money, so you can try and go to the market and buy higher level pets to explore with. You'll want the green-star ones too, since they're stronger and more likely to beat guardians that guard chests with extra silver in them.
Second is quests, and third is to simply Pound pets, since it gives you 500 silver per pet you send to the Pound. an easy way to do this is to adopt a pet every day, wait out the week, then send it back. I usually only do this when I'm real desperate for silver. Lastly you can sell items and if you're lucky people wll buy them :)
(also, hint hint, when you have questions like this about gameplay, it would be more helpful to put them under the "Help" section of the forum under the General boards)
"Violence for violence is the rule of beasts." -obama in some guy's dream
DA: https://www.deviantart.com/rawrzskythrone