How do i make a spoiler??!?

The title says it  :004j:

Click on your username in the top right have corner → My Profile → Edit my profile (black box also top RH corner) → Signature (list of option down the left) → Edit Signature

Like this:

[spoiler]Hidden content here[/spoiler]


Basically wrap the desired portion of content with spoiler tags - [spoiler] … [/spoiler]