I have to write an apology letter to a student because I called him a boso...?

Well we were playing kickball, and this dude Preston was playing and he was on my team. He called me something (i cant remember what it was) and I just ignored it. Then I was talking to a dude Alex and I'm like "Preston is a boso." and Preston heard me and he told the teacher because he's a little itty bitty wittle tattletale. And his teacher is a b****, and I mean it, she is ******* MEAN. So shes like "Okay, smart one, go call your parents bosos tonight and also call yourself a boso. Now you have to write an apology letter to Preston." So she wanted me to do it right away, but the bell rang and my very nice teacher said that I had to do it tomarrow. Everyone thought it was gay that I had to write an apology letter to him because I called him a boso.. so any suggestions on what I should write? Cursive? Printing? What should I write? Thanks.