I get involved in the convention. I joined staff this year for Kumoricon and go to the monthly meetings. It helps fill that gap.
My friends and I have started monthly photoshoots as well which is great. It motivates me to get costumes done and I get to see my friends.
Like people have said, I get planing and working as well. I've started a few costumes now for next Kumoricon (which is at the end of summer). My friend and I are also working on our skit now so we don't have to rush.
Stuff I hope to do by the end of the year:
Prism - Original design: Done except for the bow
Akihito Kanbara (Idol) - Kyoukai no Kanata: Need to add details
Drag Cloud - Final Fantasy 7: Need dress, wig and braids
Princess Daisy - Mario: Haven't even started
Bahamut - Final Fantasy 4: I need wig, and to make the wings
The Best Costume Ever - It's a surprise: All I need is the wig!