Yes. You need to use the following code: [spoiler=ID][/spoiler] where ID can be anything. The code needs to be unique or it may open someone else's spoiler tag. I usually just use my username initials, so you could use:
Hey Shadow you asked me to resize my plat card would using a spoiler be ok? And if so how do i enable a spoiler to it? I checked the thread and it said something about number varibles and i don't get what to do