I have been fortunate enough to have a very acute sense of smell from my early childhood. Smells that I didn't like but now I love are oud (Subcontinent varieties), common jasmine, champaca, betel leaf, clary sage, Zdravetz, Geranium, smoke tree, jade wood and some animalics - some of which I only like in blends (for obvious reason).
To train my nose, I have been buying single oils. I apply each neat on my skin (with a few exceptions) and then write down as much as possible about it. It is easier for me to recall them if I write things down. I regularly visit them to refresh my memory, and in the process I detect more nuances (& those go into my notes). Sometimes, I even draw graphs when I acquire similar oils from different cultivars!
Not a vegetarian. But I'm quite picky. I still cannot stand the smell of dry fish (locally we call them shutki), jackfruit (our national fruit),
Hilsa Ilisha (our national fish), cow stomach (the whole family love it) which will be very popular after Eid Al Adjha, and few more 'special' dishes! A very close friend of mine wonders if I'm really a Bangladeshi!