To start trading you will need to enable tokens.
Enabling your tokens is what makes it possible to safely trade from your own wallet. This is done by using part of the ERC-20 standard known as Token Allowance. We built a stand alone website to explain what it is and why it's needed called tokenallowance.io.
You do not need to enable the token allowance to receive a token in a trade, only to send it as part of your trade.
Can I just enable them all at once?
Unfortunately you can't. In order to enable a token you must send a transaction to that specific token contract. This means each token requires its own transaction to be enabled.
You will need ETH in your wallet to enable tokens.
Make sure the wallet you connect has a small amount of ETH in it to pay for transaction costs when enabling tokens.
You can only enable tokens you have.
Because you only need to enable tokens you are selling, tokens you don't own won't appear in the wallet.
You will need to enable WETH and ZRX to trade for other tokens.
You will need to enable any token you plan on selling for another one. Enabling WETH will allow you to buy other tokens with WETH. If you want to sell a token for WETH, you will need to enable that token. ZRX will be used to pay for relayer fees, so it must also be enabled no matter the tokens you're trading.
How to Enable Tokens
Open the wallet and click the grey toggle on the right side of the token you wish to trade.
Next select the gas price and confirm the transaction with your wallet. The gas price will affect how fast the token allowance transaction is processed. Higher gas prices will mean faster transactions.
Once the transaction is complete the toggle will be green, showing that the token allowance is enabled.