In the Signature Options you will see an icon of the Earth with a link. Just click that and it should give you the option of using URL tags before/after your link.
2014 - Upcoming Conventions :
Holiday Matsuri (FL)
Upcoming costumes : Suzie Q from JoJo's Bizarre Adventure, Edea Lee (various versions) from Bravely Default, Robotnik (genderbend) from Sonic, and more!