You've created your spell. Did you write down the associations you researched, noting why you went with one herb/color/sephirah/etc over the others? If not - do it now. I'll wait.
THIS is EXACTLY the type of stuff that goes in your Book of Lights and Shadows - your research, your decisions, the reasoning behind your decisions. And once your do the spell, you write down how well the results were. I think of a Book of Lights and Shadows the same way I think of a lab notebook for a scientist. Also after the spell, maybe after letting it 'set' for 24 hours, record your impressions of energy work, spirit involvement, etc from the working of the spell. I was taught by Isaac Bonewits to NOT review/dissect that part right after the spell, because it can lead to problems with the "suspension of disbelief" one assumes during the spellwork.
Later, you should go over the spell - and you'll know what you did, and why. You'll have written down what worked, and what didn't. You can then start to analyze WHY things worked or didn't.
You're not recording this stuff just so you have a big BOLS, you are recording the stuff AND GOING OVER IT. That is the way you improve.