Putting living heads in jars is quite a process in Vanilla Minecraft, but is possible and quite easy if you have a handsome and genius mind helping you (I'm the handsome genius). This only requires 3 simple steps to do, and looks really effective in maps, servers, or even in your normal creative world! There are three simple steps to doing this:

1. Put a hole in the floor and fill it with no more nor less than 5 layers of snow.

2. Place a command block ONE BLOCK ABOVE the hole, NOT IN, and paste this command into it:
This command summons a skeleton with your desired player head and text above their head. This skeleton will not move nor attack, but can look around, creating the illusion of the living head.

3. Place a block above the skeleton's head, stand on top of it, and type in the following commands in CHAT:
These may not seem like they do much, but these commands are what create the illusion of the head in a jar. The glass block being the jar, and the quartz pillar being its stand.

And there you go! Your very own troph... uh... effective decorative item that looks really cool for your very own world! Be sure to subscribe to my YouTube Channel by clicking this link, and also subscribe to my account to see more tutorials, maps, and handsomen... I mean, help with commands and redstone!