These are nice ways to get bitcoin what I have read so far, I personally like signature campaigns the most and am trying to become more active on the forums so I can join in on one.
Besides that I think trading might be interested to look into as well for me.
Trading is obviously one of the best ways of getting bitcoins if someone has the capital to start trading with it because trading needs basic investment in order to earn bitcoins out of it, while signature campaign does not need anything like that but the profits you get from trading are way higher than what you will earn from a campaign.