Hi. Yeah I tend to write separate sections and go back and forth expanding on them and interlinking where possible. When I've written about 2/3rds of the content I move parts about to try and give it a more cohesive structure. As for content I like to use situational references, ie. referencing whoever the other person recently battled, or else name-flips etc, and more generic stuff just as filler for the rhyme schemes. If I'm out of ideas I find scrabble helper websites can be good for wordplay based name-flips; you can search for words containing (starting or finishing with) their name or a shortened version of it, and then scan the results for any that sound like the name and another word in sequence and can be used for wordplay.