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3.example if you have 1 btc before the snapshot of BTG .now send another .1 btc to this address.
4.Now you can spend your bitcoin from your main wallet cause that previous 1 btc only had the risk to replayed .
but now as you have 1.1 btc it will not get replayed.
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Thats not true. Even if you send 0.1 btc to an address containing 1 btc, a transaction can still be replayed.
The current respectively the snapshot balance of the address does have no influence on the transaction which still can be replayed (because its a valid transaction).
But replaying this transaction would just make funds move to another wallet still in control of OP.
To be safe from replay attacks you basically "just" have to move your btc out of your current wallet.
Then, after BTG went live, you are able to import your "old" private keys to spend your BTG.
Or, in this case, OP can create a new "account" on his ledger nano to move btc funds there. Then, after btg went live, funds will appear under BTG chain (at main account).