Tables are the first item you can purchase thru the Meth App in your Laptop:
Once they have a table they can place it anywhere and start cooking:
You have a 3 sliders minigame where depending of the input and your unique strain you will receive a certain purity... Meth tables can't reach 100% purity, only meth labs can.
After cooking, players will receive (1 - 2) meth batch, they'll need the item called baggies to convert the batch to 1g bags and sell them in the streets. There's also a player and table cooldown, to prevent any type of farm. You will see this message if you or the table are in cooldown: