The first and usually only step is to download all your data from RuDEX and upload it to Koinly. There are a few ways you can do this:
If you want to import CSV files, you must make sure to import your deposits/withdrawals and trades for ALL previous years and not just the current one!
That's pretty much it. The only other thing to be vary of is to tag your airdrops/forks so they show up as Income on your generated cryptocurrency tax reports!