Dispalay a 3d model on GUI

Hi,everyone,I just making a web game,And Then I want to display a 3d model of character on the GUI.But something terrible comes to me.I have found some solutions for it ,as I thought,they told me to create two cameras ,and to assign a render texture to one of the two camera.I had a try but failed.I have no ideal about it.When I dragging the render texture to a cube and it worked well but the GUI drawtexture methond not.If anybody have some suggestion ?For appreciate!:D