Pencilling

Pencil \Pen"cil\, v. t. [imp. & p. p. {Penciled}or {Pencilled};
   p. pr. & vb. n. {Penciling} or {Pencilling}.]
   To write or mark with a pencil; to paint or to draw.
   --Cowper.
   [1913 Webster]

         Where nature pencils butterflies on flowers. --Harte.
   [1913 Webster]

   {pencil in} to write (a tentative appoinment) on an
      appointment calendar, so as to reserve time, but to allow
      the appointment to be readily canceled and replaced with
      another; -- also used figuratively, with other means of
      recording appointments. The notion being that something
      written in pencil can be more easily changed than
      something written in ink. The phrase is commonly used in
      the early stages of organizing a meeting of multiple
      persons, before it is known whether all attendees will be
      free at the suggested time.
      [PJC]