Moon phase and day of the week.
I don't use many ingridients, I work with candles, oils and herbs mostly. I don't like incences, they distract me too much.
I like improvising, just adding whatever I feel suits the particular spell, and it seems to work best that way. Not just researching it and doing it how it is recommended, I do what I feel is best. And it works.I didn't have much success with doing spells as told by someone - I guess that a spell works best if it's personal and means something to YOU.
I've used weird things and I'm not sure if many others do it, but if something reminds me of a certain person/situation/wish/whatever, I just use it in the spell where needed. It doesn't have to actually represent that to others too, what matters is what it means to ME.
I also don't add anything in my Book of Shadows, I don't really have a BoS, I have a little notebook where I put info I'd like to remember - just tips, facts, etc.
But I don't write my spells down, since I don't use spells two times. If I re - do a spell, it doesn't work. I tried and it just doesn't... I guess my spells are one - time spells and that's it.
Basically - do whatever you feel is right and you think will work. I sometimes don't take advice because I don't feel comfortable with it and my spells work out.
So - do as you feel is best.
Good luck! :)