Guacamole should be made ju003cstrongu003eust before servingu003c/strongu003e because the avocados will start to brown after about half hour, even if lime is added to it! If you absolutely NEED to make your guacamole a couple hours ahead, transfer it to an airtight container and place plastic directly on it, covering the guacamole. Close the lid and store it in the fridge until you’re ready to serve.