Theme how do i make a theme for sony ericsson P990i especially when you write messages

You can also try using a simpler application to create a theme by going to www.zedge.net you just have to register.

Its very very easy, there is special software that can create themes for most SE phone's I use it all the time.

just google "sony-ericsson theme creator" and download it from one of the links

also if you want to download a theme that someone else has made try deviant art they have heaps of them

hope this helps