A few years ago, I asked some teenage girls I was teaching who got to decide who was beautiful and what was in style. They realized they didn’t know, so we talked about the media and some of the self-centered reasons fashion trends were created and why some looks were considered to be beautiful and some were not. We learned the definition of beauty changed often. If fashion and beauty often change, they are man-made, not God-made. Truth never changes, but fashion often does. Since they could not control what the world would decide was beautiful, they realized they should focus their time and energy not on being beautiful outside, but on being beautiful inside.
There’s nothing wrong with enjoying pretty clothes, nice hairstyles, or modest amounts of make-up as long as that doesn’t become the focus of our life. Those things matter only during our lifetime and have no impact on our eternal lives.
Listen to President Uchtdorf as he talks about knowing our true identities, as determined by God, not the world.