Open Question: How to Change Picture in WIKIA ? Example I want to main change picture of 90210.wikia.com/wiki/Erin_Silver how?

I Registered in WIKIA and I Want to Change Main Picture ! How To ? There is no a any Options where as there are to EDIT Season 1,2,3 etc and Personal Life ... or upload pictures but how to change the main / Big picture ? please help me and advance thanks ... !