This command will open up the looks menu so that you can change the look (e.g. hair, eyes, etc) of your character.
showlooksmenu player 1
showlooksmenu player 1
Although the slowlooksmenu command does have other uses (like modifying the looks of other NPCs), this is the only example we can offer as this page is dedicated to the player's look menu (and not other characters). This command will open up the looks menu and allow you to modify the appearance of your Fallout character.