Never be afraid to stand up for what you believe in. People notice you, respect you, and you never know whose life you might change just by being true to yourself.
They say "No one is perfect until you fall in love with them". But I have come to disagree, in a way. Maybe being in love with someone is knowing all their faults, all their imperfections, and by knowing them you love them all the more. You love them, not despite of everything, but because of everything. You love them because you know, deep in your soul, that all of the little things that may be imperfect don't matter in the long run, and you know your life without their imperfect self is empty and lonely. They may be imperfect, but they're perfect for you.
Never promise someone that you will never hurt them, and never expect someone to promise they will never hurt you. It's impossible. Go into relationships knowing you WILL be hurt at one point, be prepared, understand that everyone makes mistakes, and give unconditional love anyway. Without pain, we would never grow. Grow, and cry, and heal, and love.
A perfect kiss is not perfect because of the circumstances surrounding it, no matter what you might have heard from Cinderella or Sleeping Beauty. It is perfect because it's his lips and your lips, his breath and your breath, his soul and your soul, intermingled to make one perfect being, and right then, all time stands still and you can live for eternity in this one perfect moment.