This perk is of questionable value unless you already have the Swift Learner perk at level 3 and want to increase gaining of experience even more, such as for obtaining the level 30 achievements. Also neither of the experience-gaining perks have any benefit past the player level cap, and thus they generally "waste" a perk slot.
Taking Swift Learner instead of this grants you permanent 10% exp boost with no matter of sleeping. But, being well rested along with having the level 3 perk will double this exp boost.
The picture is similar to that of the Mister Sandman picture, excluding the murderer with the knife and the top or only mattress. It shows the Vault Boy sleeping on a bed of spikes.
Beds flagged as owned (red name) cannot be rested in even with this perk, keep this in mind if scouting for a non-standard home to use with the perk.