I take 10 g a day and have maybe noticed muscles seem to bulk more after a hard strength workout. But other than that I feel about the same.
More water in the muscles is another effect. Also placebo. I do notice I'm a bit heavier when I'm on creatine.
Creatine is known to give you some more energy. Like, 3%-5%. That's just an extra rep, hardly noticeable.
I've recently started taking it and I've definitely noticed improved cognitive function. obviously all anecdotal and likely other contributing factors too (have been exercising more)..