For anybody still struggling a wee bit, I'm indebted to Meebo for this idea - here's a sample tweet text that will work. You can use as is or edit to suit, whichever you prefer.
YDC charity auctions start 24th October on eBid.net - follow @YDC_Fundraising for regular updates. This month's nominated charity is @rmhc
Dress that up to win the competition!