No, you don’t have to issue the coins manually. When you create your own coins, the smart contract will take care of the “issuing coins” part. (Visit https://www.ethereum.org/token to know more)
The process for the smart contract is as follows:
- You write the smart contract and deploy it
- Your investors send Ether to the smart contract during the ICO period
- The smart contract releases the tokens to them automatically through the code you have written
And creating a wallet for your coin or not is completely left to you and the functions. But in most cases you will need a developer to write the code for smart contract.