The first and usually only step is to download all your data from BW.com and import it into Koinly. There are a few ways you can do that:
Note that if you want to use CSV files, you must make sure to import your deposits/withdrawals and trades for ALL years and not just the current one!
That's all you have to do. Don't forget to tag your airdrops/forks so they show up as Income on your generated crypto tax forms!