Restore the model database:
Load your backup of model, if you keep a backup.
If you do not have a backup, run the installmodel script, which is, on most platforms:
cd $SYBASE/$SYBASE_ASE/scripts isql -Usa -Ppassword -Sserver_name < installmodel
On Windows:
cd $SYBASE/$SYBASE_ASE/scripts isql -Usa -Ppassword -Sserver_name < instmodl
Redo any changes you made to model.
