Explaining to someone about how much you like them?

I have this thing, with a girl i ADORE, shes my world, and we've had things in the past. Shes a year older, and she hates it, because im a year below. I want to convince her about these things. Im year 10, and shes year 11. shes my world, she means everything to be, i've had a softspot for her ever since i met her. i just want exact words, to say to her. Perfect words, that'll help me, after two years of trying. Help me to win her heart