How do I display my current grows in my signature??

hello,

Ive got a few grows going right now, and have seen how some of you guys have links to multiple grows in your sig. When i try to put the links for mine, it says there's not enough room. am I doin somethin wrong, or can I just put one grow in my signature? kinda confused, any help appreciated

What do you have the text size on? I use the smallest size.