The first and usually the only step is to download all your data from omniwallet and upload it into Koinly. There are a few ways you can do this:
Note that if you decide to import CSV files, you have to make sure to import your deposits/withdrawals and trades for ALL years !
That's it. The only other thing to be vary of is to tag your airdrops/forks so they appear as Income on your generated crypto tax documents!