For BPAL, if you want to seriously sample it, you'll have to leave it on for a bit - they usually change within a few minutes as it dries, and then have some slower changes over a few hours. I usually use the wand tip on the cap, swipe it on the inside of one wrist, rub my wrists together, and then rub them on the sides of my neck.

If you're doing shorter sample tests (ie, through drydown but not really any longer) I tend to do little swipes on the inside of my arm or back of my hand. Soap and water will clear most of the oil's smell away, and having some fresh coffee beans to sniff inbetween samples helps clear your sense of smell some (and I say this as someone who hates coffee)