You will have to use collision groups on the client to do this. For the BaseParts that you want only collidable by the local player, you set their collision group to something like LocalPlayerGroup. Then on that client, you set every other characters (excluding their own) BaseParts to a different group like OtherPlayers. Then you set those two groups to not collide with each other
You did the 3 steps correctly, however I want it so the players can go through each other. But when I did your example, the players couldn’t go through each other.