Use Bedrolls [Updated for 1.6]
Original mod by Uuugggg. RIP.
Bedrolls are used from the inventory. When a pawn needs to rest but can't find a bed, he'll place a bedroll from his inventory.
Bedrolls are picked back up after sleeping.
Bedrolls are shared amongst members of a caravan: they will all have one so you don't need to find a bedroll from someone else.
(This all technically applies to any type of bed, if you can get a pawn to hold it.)
Bedrolls can be created at tailoring benches (in minified form instead of a constructed building)
Check Steam page for any updated info.