Of course nobody can tell you this, but the coins I expect to grow a lot in 2018 are Aeternitys AE and Ardors ARDR. Both projects will launch their mainnet and will become very popular if they deliver what they promise. Ardor actually already delivered with testnet. We will see, but Im very bullish on those two.
None of us knows the answer, but we can make predictions all the time.
For me, waves, monero, oax, binance and omisego will be the next big things in 2018. They can easily make 10x or 20x rise.