You can spend to trade or sign some campigne or look for a bounty in this forum.
yep trading and joining signature campaign and social campaign that you will earn bitcoin, If you want to get extra bitcoin try to look micro earning sections you can find many site that you can earn more.
to me i think if you have a little money to invest then you can also get good profit from bitcoin, signature campaign income can be limited but from trading you can even get unlimited income from trading altcoin. but while trading you need to have good experience in trading.
Better idea since provably theirs a lot of people that cannot afford to buy some bitcoin right now since at this rate bitcoins is pretty expensive and that can actually make unreachable for people who has limited budget in their pockets. And signature campaign earnings would be the best way to earn free and we can used it on tradings aswell as in different place where we can earn more.