There is no optimal time to take creatine.
Creatine isn’t like some other ingredients—say caffeine—where you take it once and then “boom,” you have an effect! Instead, it builds up and ultimately saturates muscle cells over time. Once the muscle cell is completely saturated, creatine is able to have its greatest impact on power and strength.
It typically takes around 30 days to fully saturate your muscles at the recommended dose. So instead of focusing on taking creatine at the optimal time (which doesn’t exist), simply remember to take it every day.