The sorting in Ilvernormy is different from Hogwarts. So read this for sure before you plan to RP out your characters sorting ceremony.
How it happens by steps:
1) When your character starts her education in Ilvernormy she/he will step onto a Gordian Knot on the floor in the centre of the Entrance Hall where large statues of the mascots for the four houses is. You will have to face it.
2) The carved statues react if they want the student to be in their house.
3) The carvings react following way:
Horned Serpent - The crystal in the carving's forehead glows.
Wampus - The carving roars.
Thunderbird - The carving beats its wings.
Pukwudgie - The carving raises its arrow.
4) If more than one carving reacts then the students can choose which house she/he wants to be in. (Remember this happens barely, it's rare as once a decade or even generation. Rarer is that all of them react).
5) After house is chosen then the student will be chosen once more, this time by a wand.
6) Students can't have wands before the sorting and they need to leave their wands at school if they go to holiday breaks for home. You can use wands out of school when you have reached to seventeen.