The first - and in most cases the only - step is to download all your transaction data from bread wallet and import them into Koinly. There are a few ways you can do this:
If you decide to use CSV files, you must make sure to import your deposits/withdrawals and trades for ALL previous years !
That's pretty much it. The only other thing to be vary of is to tag your airdrops/forks so they appear as Income on your final crypto tax documents!