What is the best way to paint over semi gloss paint?

I want to paint over my kitchen walls that are currently painted with a semi gloss paint.What is the best way to paint over semi gloss paint?
Go to your paint store and ask for De-glosser. It comes in gallon containers and you apply it just like if you were washing the walls. Wear gloves and eye protection, and ventilate the room. Then go ahead and paint after 24 hours! Have fun!What is the best way to paint over semi gloss paint?
Was this semi gloss oil based? Most of the time it's water based and if so there is no problem. If you put a water based paint over an oil based paint though it may look good for a while but then it will start cracking and peeling off.





so, if it's oil based, put an oil based paint over it.
sand the walls first then apply a good primer. I always feel it is worth spending more on a good primer as that way your paint will go on well
KITCHEN walls are notoriously harder to deal with because of the light coating of oil on them...





SO! A scrubbing with something like TSP is mandatory and a light sanding like the first Answerer may be required for old and cracked paint.





Next step is a good primer. A lot of people don't understand that primer is not simply a white paint used for color applications...or something (I have heard a lot of weird ideas about what primer is...)





Primer is a medium that is applied to better adhere one paint to another...It is not the same as paint! So a different primer is required for an original existing paint-job that was an oil-based paint to a new latex paint than one that is old latex to new latex.... and there are other considerations...like were there awful things that happened in a house like people and animals dying there so that you need to seal up all surfaces because odors have permeated woods and wallboards?...in that case the only successful paint-jobs require a very expensive primer before any quality paint.





Primer is the key along with the correct amount of surface prep...if you skimp on the beginning stuff it will look Okay but won't last...Nuff said. If you're painting over old paint-Sand...otherwise since it is a kitchen---clean thoroughly before you prime and paint!
prime the walls first and than your finish coat
If the original paint is oil based use an oil based eggshell or similar - if it water based 'vinyl' or 'acrylic' you should be able to recoat with a similar paint. If you are wanting to change from oil based to water - use a matt primer first.
just put a primer over it.and then what you want for a paint you will be all set the primer will hold to any paint you pick.
You'll have to rub them down with sandpaper to make a ';key'; for the new paint to bond to...