Here's what you should do...
The first and usually only step is to download all your transactions from Aphelion and upload them to Koinly. There are a couple of ways you can do that:
- Aphelion does not offer any API, so you will need to download your transaction files from their website and upload them into Koinly yourself.
- If the above method(s) is not possible for you, you can also add the transactions one by one through Koinly's web interface.
If you decide to import CSV files, you have to make sure to import your deposits/withdrawals and trades for ALL previous years - not just the current one!
That's it. Don't forget to tag your airdrops/forks so they appear as Income on your final cryptocurrency tax reports!