Well eveybody is agree that only signature campaign is the safest way we all know to grow your bitcoins, and some others are saying go into faucets. But faucet needs to be exert more effort and hard work.
With signature campaigns you can earn coins, but to grow amount you already have you need to invest in something.
Let's be clear what we talking about here. Trading is similar with gambling, cloud mining and landing sites are not safe at all in my opinion.
So million dollar question, how to grow bitcoin amount safly? No how, risk and make more, don't risk and be satisfied with PTC sites, signature campaigns, etc...