yeah...maybe a little acid was dropped as well. "She combs her hair" seems to be a low bar for a guy like Mick. Regardless, I always get a kick out of what must go into the artistic process to come up with these lyrics, tunes and arrangements. Where and how do you get some kind of consensus with the artists, labels and others to say "That works! Done!".
"She's A Rainbow" is a fantastic song. I recall reading once where Mick said that while he really likes it, he didn't have anything to do with writing it and Keith wrote it all, but I can't find it now so maybe I was imagining it.
I fool around on the piano a little now and then, very slowly learning stuff. Now and then to keep me motivated I'll go you Youtube and find a tutorial and learn to play a bit of a song I like. I did it a few times with the piano intro to She's A Rainbow but I'd always forget.
But if you learn scales, as I'm doing gradually, it becomes a lot easier. Now that I know the B flat major scale, I immediately see that She's A Rainbow is right from it.
A scale is typically 1-2-3-4-5-6-7-8. For She's A Rainbow, drop the 1 and switch the 7 and 8. So in the B flat major key, play 2-3-4-5-6-8-7 and that's the beginning. Of course, since you're not playing 1 you're not actually playing the B flat key. The B flat key, BTW, is the rightmost black key in the clump of 3 black keys.
Major scales are 2-2-1-2-2-2-1. The number are the number of half steps you go up. So if you start at C and do the above pattern you see you hit only white keys, which is why beginners like the C major scale, since it doesn't involve the black keys, which are intimidating when you're first starting.
Start at the B flat key and do that same pattern and you're in the key of B flat major. Play 2-3-4-5-6-8-7 in that key and you're doing She's A Rainbow.