If you have a huge amount of BTC, you just hold and you will get big profit. But if you just have a little BTC and wanna grow it, you can invest in ICO projects. Playkey is an example for you
This, just start off with buying as much of the big name 3 coins that are going to go up like BTC/LTC/ETH and check back in a few months or start with a super small amount like $20 and dive head in trading and learn as much as you can with your first gains and losses for the first couple of months then scale up from there.