If you can smell perfume in person before buying it, take advantage of that.
But don't stop at smelling the bottle.
Fragrance develops on skin, so wearing it can tell you much more about whether it actually suits you.
If you are buying online, start with scent profiles related to fragrances you already know you enjoy.
Oud and strongly woody scents can be more of an acquired taste for someone unfamiliar with them. If you are completely new to those styles, beginning closer to your normal preferences may be easier.
When your new perfume arrives, start with one light pass on a small area.
Give it time before deciding.
A fragrance deserves more than a three-second sniff.