How to change a players character / look mid-game?

i want the player to be able to click on a gui button and change the look of the player's character to a pre-built character.

I have tried copying the model into StarterPlayer and changing its name to 'StarterCharacter' (when the button is clicked) but that did not work.

I have tried removing all of the children of the player.Character and cloning in the children from my pre-built character.

I have also tried just setting the player.Character = game.Workspace.mycustomcharacter but nothing is working.

Can someone please put me on the right track with the best way to do this? I have seen this working in many games, but I can't find a good tutorial to walk me through it, and I am pretty new to lua scripting.

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update: this sort of works:

local player = game.Players.LocalPlayer player.Character = workspace.mycustomcharacter

but the camera does not follow and the arms, legs etc. do not animate.

am i on the right track? or is there a better approach?

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so i got the camera to follow using:

cam = workspace.CurrentCamera cam.CameraSubject = player.Character.Humanoid

but even though the character moves around, the legs, arms, etc still don't animate.