Mist Wallet with the Hard Fork option activated (when prompted on startup, select 'Yes')
Loaded Mist account(s) with ETH that you wish to split between the chains.
Separate accounts for each chain. You can either create new accounts in Mist, or use another wallet provider/exchange. I would highly recommend only using Mist for one chain, and some other provider for the other (another computer will work as well). Otherwise you will need to switch between chains and re-sync Mist every time. I used Mist for ETH and Poloniex for ETC.
Step 1: Adding the Split Contract
In order to split the same ETH into ETH/ETC on two separate accounts, we'll make use of a contract designed to split funds between chains and which was deployed before the hard fork. It is now in a different state on each chain and will send to a different address in each version. The contract details can be found here. I encourage you to look over the code yourself and not trust my word for it. If you are unsure, have someone you trust check the code for you to ensure it's doing what you intend and that I'm not simply stealing your funds ;)
In Mist, navigate over to the 'CONTRACTS' tab.
Under 'CUSTOM CONTRACTS', click 'WATCH CONTRACT'
Fill in these details:
CONTRACT NAME: ReplaySafeSplit CONTRACT ADDRESS:
0xaa1a6e3e6ef20068f7f8d8c835d2d22fd5116444 JSON INTERFACE:
You should now have a new contract listed under CUSTOM CONTRACTS called 'ReplaySafeSplit'.
Step 2: Calling the Split Function on the Contract
Now that we've added the contract let's click on it. It should look something like this:
Under 'WRITE TO CONTRACT' there's a dropdown with only 1 option called 'Split'. Let's select it.
THIS IS THE IMPORTANT PART
The 'Target fork' field is the address of the ETH account you will use
The 'Target no fork' field is the address of the ETC account you will use
DON'T MIX THESE UP!!!!!
Fill in these fields with your two separate accounts. Double check that they are correct. Send whatever amount of ETH you would like to split between the chains.
Step 3: Keep Them Separate
You now have ETH/ETC in separate accounts on each chain. In order to avoid confusion and mistakes keep these separate going forward. Don't send ETC into your ETH account or vice-versa.
Hope this was useful to some of you and that you can now make your own decisions about which version of Ethereum reality you choose, or choose not, to participate in.
read more at : https://steemit.com/ethereum/@pauls/ethereum-fork-step-by-step-guide-to-safely-splitting-your-eth-etc