1. You can’t show it all
…so figure out what’s most important and find a way to demonstrate that. It will be different for every piece. DO NOT give a play-by-play account in your analysis. The inventory of events that happen is one step on the way to understanding how the piece works, but in itself, it is not an analysis.
2. Mixed approaches to notation
Stockhausen, Study II (1954) was completely scientific in its approach, but you miss the musical relationships. This animated version helps.
Stockhausen, Kontakte (1960; excerpt) uses a combination of multiple staves, shapes suggestive of scientific parameters, shapes suggestive of traditional music notation, and plain words (which are in his native language, German):
Luening/Ussachevsky, Incantation (1953) was an early composition made by editing sounds recorded on tape. Modern scholar Brian Evans made a graphic score of it using only a few symbols, and marking its sections. He clearly didn’t notate every single sound.
3. Relationships, not just a list of sounds
Harvey, Mortuos Plango, Vivos Voco (1980) only has two sound sources in it, so Dr. Evans had to focus on how the sounds were transformed, more than an inventory of which sound happened when.
See more examples and discussion on graphic scores here.