Get Text from Current Line

[Jeckob]

Hi,
i would like to write some code in emacs-lisp to format/align the
current line in a spec. way each time the editor jumps to the
next/other line.
i.e.
when i type:

abc xyz kfx uzr ert : ert : oiu

the editor should format it the moment i type enter or nextline (arrow
down) this way:

abc       xyz       kfx       uzr       ert       : ert       : oiu

and so on....

How can i realize this? Pls give me a hint, dont how to start !?
Thanks