I used to use the "/" as the snare for my lyrics, but I would lose track of the rhythm. Then I used it to denote breaths, strictly for my own purposes regarding phrasing. Now, if I'm writing on full sized paper (ie notebook paper) I just do what you do, which is start a new line. When writing in my composition notebooks I still sometimes write with the /s. I've noticed patterns in certain rapper's lyrics when reading them off the page. For example, after reading Tupac's poetry book, I noticed where he writes the breaks and where he recites them are completely different. I don't know if it's because he was extremely insistent on only using the first vocal take (he liked the way it 'comes off', sounding more passionate) or if it was because he liked to write breaks in his raps so that if you're reading them they're easier to understand vs listening to them. Esham doesn't put the breaks in his lyrics at all, they are literally one long ass line of jumbled mess and I have no fucking clue how he makes sense of them at all. The only advantage to that, I would think, is that you don't limit yourself to one style or flow, and you can experiment as you record. Eminem is another mc whose breaks don't seem to make any sense, usually he writes the / after the words that rhyme, but as any one who listens to Em will tell you, usually his rhymes are internal rhyme schemes so reading his lyrics can be quite confusing. Royce Da 5'9" is literally the only rapper that I could flow his lyrics nearly exactly by reading them, usually the break is on the kick, so even if his lyrics lack sense in this way by reading them outright, it's easy to know where he is putting each word (although admittedly I think I've only seen his lyrics a few times from what he's posted on twitter). Tech N9ne writes his lyrics like paragraphs, because he only writes in four bar quads, then flows out what he's written, and starts again. This is to ensure he stays on beat (given his frantic flows). But again, I have no clue how he remembers which flow is for which part, especially given how often he switches them up.