Need some help

So i bought this new coffee set and im still trying to figure out the right dosage . I tried 18g for a double basket but it was too much , how many grams should i use for double? And is this enough crema ? I think its too little , how to get more crema ? And if anyone has experience with this delonghi machine can you help me out ? And how hard should i press when i tamper the fine grounded beans ? I work as a bartender so i have experience with latte art and making coffee but where i work everything is automated, both the grinder and coffee machine . Thanks in advance