New BB Code in quick reply?

[OurCouponHome]

How do you enter new bb codes in quick reply? I thought I was doing it right but now have red x's where the pictures should go.

--------------- Added 1297794466 at 1297794466 ---------------

Nevermind! I figured it out! :)

[Videx]

That's not very helpful to future searchers. You should explain it, even if you think it's something everyone else already knows.