What to do after tree lilies bulblets come through

I don't think it makes any difference whether they are Tree Lillies or Lillies aym.

I choose only the fattest scales, sit them upright in a mixture of MPC and Perlite/Grit and just damp them.  Stick them in the Cold Frame or on windowsill ( depends on time of year you are doing ) and wait for shoots to show.  Works ok for me