GC Fever
It is always better (and INS also recommends it) to apply renewal at least 90 days before expiry. Yes, you can do without attorney. The form is very simple, and can fill it out in less than 5 mins.
Why 90 days? As we all know, INS is very very unpredictable....if you apply before 90 days of expiry, and still don\'t get it...you can just walk to local INS office and show the receipt, and get the EAD (it is allowed by INS when the EAD application is waiting for more than 90 days)
The forms can be ordered on INS website for free. You should have received the first EAD card attached to a paper (like Credit card)...there they mention about sending that peice of paper with the renewal application (to serve faster). If you have it saved, just attach it along with the renewal.