How the house is built
Start by modelling the windows in transparent FIMO and shape the entrance door. Create marble-look polymer clay panels from the different shades of brown to form the house wall. Work the windows into the "wall". Place the modelling surface on the glass and work out the joints.
Before hardening everything in the oven at 130 °C for approx. 30 minutes, check the surface for fingerprints that have formed during modelling and remove them if necessary (simply brush over them). Once hardened, your work will remain in the modelled shape and can no longer shift.
Modelling decorative ornaments
Now you can decorate the basic shape of the witch's house as you wish. For example, twist two strands of modelling clay into each other and place them on top of each other as window frames. Mould small leaves and flowers and place them decoratively on the house. You can also harden them in the oven and fix them in place with hot glue.
Finally, place the LEDs in the glass.