Anything (doesn't have to be sexual) that makes you feel good is sensual. Like, a massage, eating chocolate, having a bath or shower, tickling, kissing and hugging, sliding your fingers on your arms and neck, etc. It could also be a nice setting or eating tasty food and drink.
Sexual sensuality is masturbation, breast and genitalia rubbing, neck kissing, body licking - feels good, eh?
Kate: Can you please massage my back?
Marcus: Yeah sure. *rubs*
Kate: Wow, that's paradise...
Marcus: Sensual, right?
Little girl: MAMA! TICKLE ME PLEASE!!!
Little girl: HAHAHAAHAHAHAH AGAIN AGAIN! DON'T STOP!!