First things first, install the vmod in your world using the link below.
Once it's installed, you'll need the advanced crafting table to use the new recipes. This is made by dropping a log of any kind and an iron ingot on the floor nearby each other.

Grass block:

6 sided logs:

Leather:

Saddle:

String:

Cobweb:

Red sand:

Packed ice:

Burger:

The burger heals 8 hunger points and heals 2 hearts, but give the player temporary slowness.

Step 1: Download and run minecraft on the latest 1.9 snapshot. As of this writing it is version 15w51b.
Step 2: Load your world, and do the following command:

/give @p minecraft:command_block

If your world has cheats disabled, you have to open to LAN and enable cheats first.
Step 3: Paste the command from the link below into the command block and set it to "Always active"

If this is done correctly, you would spawn the command block module in your world.