The first - and in most cases the only - step is to download all your transactions from BtcTurk and import it into Koinly. There are a few ways you can do this:
If you want to import CSV files, you have to make sure to import your deposits/withdrawals and trades for ALL previous years and not just the current one!
That's all you have to do. The only other thing to be vary of is to tag your airdrops/forks so they appear as Income on your final cryptocurrency tax forms!