Idliing rough sometimes

Recently had the oil change 42k 01 F150. Afterwards it started idling rough sometimes, if it is warm like above 80. Had couple of days with cooler weather 60's it started and idle smooth until the engine got warm. Also every once in a while I start it and see blue smoke. The smoke is usually it sits for day or two. I use to run valvoline now its pennzoil. Any suggestions on either of these two problems would be appreciated.
Thanks
John

What engine? I would run a fuel injector cleaner thru a tank or 2. I like chevron with techron.

sounds like bad vavle guide seals if it sits for a couple days the oil leaks pass the seal and sits in the cylinder till you start it and it burns off you can try an high mileage engine oil that will help recondishtion the seal if that don't work you'll be in for an vavle job