To 'razz' something is to use something for it's intended way, but in a cool and or stylish fashion, usually done in a
slap-dash, playful manner, usually for a
short amount of time for a quick practical or language based gag.
i.e, 'having a razz with a girl/man' would refer to having enjoyable, good sex with a partner or 'having a razz on my
guitar' can be translated into 'I quickly played my guitar'.
You: "Hey, can I have a razz on your
skateboard?!"
Them: "Sure, i Guess."
*Rides around in a
circle and attempts a kickflip which sends the board
flying*
*You and them rejoice in laughter*