If you've got your bitcoin stored on a Ledger Nano S here's a tutorial on how you can easily claim your lumens. It's a bit different compared to a "normal" wallet, mainly due to the fact that you don't just have 1 address, you more than likely have 10's or even 100's of addresses. The reason behind this is to protect your privacy, so all your transactions aren't related to just 1 bitcoin address for example.
First, go find your last transaction on your ledger, because it will contain the left over balance of your bitcoin.
For example, paste in the address (if your last transaction was outgoing) here:
https://blockchain.info
From this page get the NEW address where the remaining bitcoin balance was sent to (this is your current public address). For example if you sent .2 BTC, you would see .2 BTC going to the address you sent to and the remainder of your BTC go to a new address - this is the address that you want.
Next go to stellar page: https://www.stellar.org/lumens/bitcoin-lumen-program/
Enter your info, etc, put in your current public address from the step above.
Finally they give you a message to sign that looks like: Stellar.org Bitcoin Giveaway Round 2: SOME HASH HERE
In nano-s chrome app, go to settings -> tools -> "Sign message"
Locate the address you got on the blockchain.info above and paste in the message from stellar.
The output will look like this:
-----BEGIN BITCOIN SIGNED MESSAGE-----
Stellar.org Bitcoin Giveaway Round 2: SOME HASH HERE
-----BEGIN SIGNATURE-----
--YOUR ADDRESS WILL BE HERE--
--COPY THIS LINE ONLY--
-----END BITCOIN SIGNED MESSAGE-----
^ copy the second line under signature only and put it into the stellar web app, you should see a success message - that's it!
