I wouldn't recommend aspiring to have celebrity skin as opposed to simply healthier skin; the make-up many celebrities probably use can drastically change the way they look, so don't use that as a standard.
I suppose for better skin, do the things like:
drink water
do exercise (better when sunny), wear at-shirt as opposed to shirt in summer, so expose more skin to sunlight, protect skin from burning though, if necessary
eat healthier foods, like fruits, vegs. etc.
cut down on junk (mainly oily) foods
colder showers, tighter skin? (well cold at very end)
better shampoos, not cheap harsh stuff (have to invest a bit mor,e but well worth it, if you're not already)
for nice hair and scalp as well, try using/try out coconut oil (actually very good, try out superdrug I think (not many places sell it))
remember that showers can be harsh on skin, harsher when hotter & longer, moisturise after showers also
To look even better naked, confidence would probably be a must; remember confidence is attractive. Have good posture, don't be nervous, shy etc. Trust me confidence affects everything.