In order to increase the gas for your transaction, you will need to click the "Edit" button in the MetaMask pop-up window when it appears. This will open a window where you can adjust the gas limit and the gas price. Increasing the gas limit will allow your transaction to be processed faster, while increasing the gas price will ensure that miners will prioritize your transaction over others. Keep in mind that if you increase the gas price too much, it could become cost prohibitive. It is important to find the right balance between speed and cost.