it's in the cards menu
you can stake 1k starbits at a time

basically when someone sells an NFT track - you get a piece of the sale

i have about 100k staked atm - i'm up to 1800 starbits earned from staking - that's not a ton - but it's extra 1800 starbits i didn't have to do missions for

i just keep adding to all the stakes

only got like 900k left to reach may target LOL