Web3js smart contract interaction gas and signing

So I can interact with a function within a smart contract.
I also know that to actually do the transaction I need something like this:

const contractObj = new web3.eth.Contract(abi, contractAddress)

const transaction= await contractObj .methods.NameofTheMethod(x).send({from:myAddress,gasLimit:value})

My question is: what is the next step? Because I put myAddress but I should sign this before send the transaction right?

Otherwise how will it be able to take the fee from the gas?