If you could write a book, any book, that would explain how you crochet, what book would it be? For me, it would be one already written, Blueprint Crochet by Robyn Chachula, designer extraordinaire.
Robyn has written a great instructional treatise on how to use stitch symbols when you crochet. This is something I try to teach my students, because more and more I hear "I just can't read patterns." Or "Why can't they just say what they mean?" So - I usually sketch the pattern out for my students - with stitch symbols and diagrams. And then, they get it! They can see what they're doing because the symbols look like the stitches they represent, and the diagrams look like the fabric they're making.
I also use symbols when I'm planning a design, before I actually crochet anything. I figure out multiples, row counts, increases and decreases, and anything and everything else I might need to do with or to my pattern. I also use stitch diagrams when I'm tech editing other designers' patterns. It's a quick and accurate way to check numbers, etc.
In her book, Robyn explains how to read the diagrams, whether the pattern is in rows or rounds. Once you know how to read them, then you can see from the diagrams how to put motifs together.
The patterns in Blueprint Crochet include sweaters and totes and jewelry, and Robyn tells you the plan for each pattern, what you need to know to make the basic stitch pattern, how to construct the piece, and all about finishing it to make it look it's best! Even if you don't want to make the patterns, the information about working with and using stitch diagrams is priceless, and shouldn't be missed!
