Somewhere I saw a post where someone described little behaviours that they thought were distinct with them. I've been thinking about this some and rather than wait until I have a reasonable number of them and never get around to posting them, I thought I'd mention two that I've thought of:
Unless I'm utterly exhausted, I need some sort of cover to sleep. It can be a sheet or something else light but without that cover, I have great difficulty getting to sleep.
For a shower to feel like it is getting me clean, it has to have some warmth to it. No matter how hot I am, I need it to be a warm shower to feel clean.
I'm sure I'll come up with more. I'm not sure if I'll add to this post and point to it or just mention it in a new post...