You have to add a quite experienced player (I chose "pawned"), because
they've got more superfollowers. Once he accepts you (which will probably
happen real quick) you can visit his planet and tap on a guy with a star 
over his head. It's also possible with other guys, but you'll double your
income if you choose a star-guy. Well, next step: zoom out and click on 
any other planet he's friend with and repeat on as many planets you like.
After 6 hours you gain money depending on how many planets you visited. 
For a star-guy you should get at least 100g. This way, you can easily 
gain gold in no time...