F3 will open up the emotes menu.
Use your arrow keys Up and Down to navigate this menu.
Press Enter to open the "Emotes" selection.
You will see "Dance Emotes", "Prop Emotes", "Shared Emotes" and "Keybinds".
The "Dance Emotes", "Prop Emotes", and all of the regular emotes you see in the main list, can be bound to numpad keys 4-9. If you need more help with binding emotes, click here.
Shared Emotes require another player (and their agreement).
You can cancel any currently running emote by pressing X on your keyboard.