The first - and in most cases the only - step is to download all your data from coinrate and upload them into Koinly. There are a few ways you can do that:
If you decide to import CSV files, you need to make sure to import your deposits/withdrawals and trades for ALL years and not just the current one!
That's it. The only other thing to keep in mind is to tag your airdrops/forks so they show up as Income on your generated cryptocurrency tax reports!