To make your own Mig33 file you need to extract mig33 jar file and then edit the contents of it. To extract jar file you can use winzip or winrar. The steps are given bellow-
(*) Install winrar or winzip to your PC.
(*) Right click on the Mig33 jar file and go to open with and choose winrar archiver.
(*) Then u have to edit the .png files with any graphics editor.
(*) Copy the MANIFEST.MF to your desktop.
(*) Next open it with notepad & change the marked parts to your own name!
(*) Replace the default file with your edited file!