i read the rules but im still quite confused where to start.

once a battle is posted, it's always in "the arena" section, click on the heading, the first post is usually the info on the battle such as a song to sample as well as some drum breaks(usually), just sample the stuff you want, ONLY FROM THE SUPPLIED SOUNDS, wham bam make a song then upload it to the same thread as the battle. hopefully this helps, if not just go over some of the previous battles and see how things are laid out peace.