FORMAT KINGSTON FLASH MEMORY CARD FOR CAM

Hello,
Hello,
i have recently bought kingesten 4 GB flash and I put it in my camera .It showed out of memory . then It asked me format or not format . suddenly & accidently I choose formatting and delete a file in it . information. then to day i tried to use it but I couldnt . It showed out of memory . I dont know what to do . so can u pleash help me what to do in order to have my full 4Gb free space
thanks