Download Electrum (
https://electrum.org) or any offline wallet and send your Bitcoins to them. As long as you don't store your coins in any exchange/web wallet and you have full control over your private-keys, you will be ok.
For your Ethereum, I recommend you to use MyEtherWallet (
https://www.myetherwallet.com).
As an alternative, there is also Exodus where you can store your Bitcoins, Ethereum, Litecoin and other coins in the same software (
https://www.exodus.io).
When your Ledger arrives, store all your coins there. Don't touch them during the chain split to make sure you don't lose any Bitcoin.
