How to add weapons / props to taunts?

FancySnacks

L1: Registered
Aug 16, 2016
20
28
I'm making a halloween taunt in SFM. How do you add props / weapons to your taunt? For example, I want my Medic to reach for his back, and when the hand reaches it he grabs a potion (I want the prop to spawn at specified moment). Another example would be Second Rate Sorcery or Didgeridongo.